Why marriages last

A discussion of the literature
Research Paper No. 28 – July 2004

Longitudinal theories of marriage

How does marital happiness or satisfaction change over time? The answer appears to depend on how the measures of marital satisfaction have been obtained. It is widely accepted among researchers that satisfaction follows a Ushaped trajectory: a pattern of early decline followed by a levelling out during the parenting years and an improvement when children leave home (Van Laningham, Johnson and Amato 2001). However, there is also evidence to suggest that marital satisfaction declines regardless of the presence or absence of children (Clements, Cordova, Markman and Laurenceau 1997). In addition, other patterns of change in marital happiness have been found, with continuous declines, continuous increases, and relatively little change across the life span having been reported.

Support for the U-shaped curve tends to come from cross-sectional research (Karney and Bradbury 1997; Orbuch, House, Mero and Webster 1996), although contradictory results are to be found among such studies. Linear trends have been found via longitudinal analyses, but these studies may also be reflecting period effects (changes due simply to growing older; de Vaus 2001) rather than actual developmental changes. The issue is further complicated if satisfaction is reported retrospectively. Findings based on retrospective reports of satisfaction tend in general to be viewed with caution, although retrospective reports actually may be more accurate because the distance afforded by time provides a more balanced perspective (Mackey and O'Brien 1995).

In spite of a large body of research, there are few studies following couples over periods of more than ten years, so researchers have yet to achieve a clear understanding of the trajectory of marital satisfaction in the longer term (Van Laningham et al. 2001). As with cross-sectional studies, the outcomes of longitudinal research have also been inconsistent.

Until recent years the inconsistency of findings could have been due in part to the inability of statistical techniques to deal adequately with the extent and rate of individual change (Karney and Bradbury 1997). The problem is that while two individuals may be similarly satisfied at a given point in time, their journey to that point may have been vastly different. As well as being likely to have commenced the relationship with different levels of satisfaction, any changes in satisfaction across a given period of time may have been rapid for one individual and slow for the other; the same event may trigger a rise in satisfaction for one and a decline for the other. In addition, Karney and Coombs (2000) noted that analysing mean patterns of change can conceal variability across individuals. Although satisfaction in their sample of wives showed an overall decline across a twenty-year period, for a substantial minority of women satisfaction remained constant or increased across assessment intervals.

It will take time for studies employing advanced techniques that do allow for analysis of variability across individual trajectories to generate sufficient data to allow firm conclusions about changes in relationship patterns over extended periods.

Karney and Bradbury's Vulnerability-Stress-Adaptation model

In a landmark paper, Karney and Bradbury (1995) advanced a theoretical framework to explain changes in marital quality and stability across time and across couples. Based on their review of over 100 longitudinal studies of marriages and an evaluation of the utility of four commonly-cited theoretical perspectives - social exchange theory (as applied by Levinger 1965), attachment theory (Bowlby 1969), crisis theory (as described by McCubbin and Patterson 1982), and behavioural theory - Karney and Bradbury identified some general themes that could provide the basis for understanding how and why marriages survive or break down.

Elements of the four theories highlight aspects of relationships that can provide the foundations for an integrated theoretical framework. For instance, social exchange theory suggests that the perception of a relationship is coloured by the rewards and costs associated with the relationship, the sort of relationship the individual thinks he or she deserves and their perception of the rewards and costs of being in a relationship with someone else. Attachment theory specifies certain characteristics of each partner that will contribute to the functioning of the relationship. Crisis theory suggests that events such as the transition to parenthood or the experience of unemployment will have an impact on marital quality. Behavioural theory points to the importance of couple interaction and how members of couples cope with relational issues, conflicts and transitions.

Based on their analyses of previous research, Karney and Bradbury identified three classes of variables that, when combined in a single framework, optimise what we can learn about the processes by which marital satisfaction and stability change over time. The three key elements of their theory are outlined below. The relationship of the elements to each other is presented in Figure 1.

Figure 1. A vulnerability-stress-adaptation model of marriage

Figure 1. A vulnerability-stress-adaptation model of marriage, described in text.

  • Enduring vulnerabilities: the individual strengths and weaknesses each spouse brings to the relationship. These stable characteristics can include their personality, beliefs and attitudes about marriage, their family of origin and social background.
  • Stressful life events: incidents, transitions, or circumstances encountered by the couple that can impinge on their relationship and create tension or stress.
  • Adaptive processes: the ways in which a couple addresses conflict, how they communicate, how they support each other and the ways in which they think about marriage, their spouse and their spouse's behaviour.

According to Karney and Bradbury's model, the ways in which couples deal with the life events they encounter are the key contributors to the couple's perceptions of the quality of their marriage. The couple's adaptive processes are a product of the interaction between the individual spouse's enduring vulnerabilities and the type and severity of the life events they encounter. Thus satisfaction and stability may be relatively high for a couple who have few enduring vulnerabilities and poor adaptive processes if those qualities are tested infrequently. On the other hand, repeated or chronic exposure to stressful events may test even those marriages where the spouses are normally well equipped in terms of their individual capacities to cope and their particular patterns of interaction. As Halford (2000) points out, life events can have both negative and positive effects on a relationship depending on the strength of the couple's adaptive processes.

A couple's accrued experience in dealing with difficult or stressful circumstances will alter spouses' perceptions of the quality of their relationship and vice-versa: satisfaction with the marriage is likely to lead to more positive interactions and behaviours, while engaging in positive interactions and behaviour is likely to enhance marital satisfaction and perceptions of quality. Alternatively, unrealistic expectations or dysfunctional patterns of communication may increase the likelihood of relationship problems and declines in satisfaction over time (Olsen and Fowers 1986; Olsen and Larsen 1989; Sanders, Halford and Behrens 1999). Ultimately, repeated failures of adaptation will undermine the stability of the marriage, leading to increasing frequency of thoughts of divorce; successful adaptation will strengthen or maintain the relationship and reduce the chances of eventual dissolution of the marriage.

Karney and Bradbury's (1995) theory incorporates personality, family variables, and life events into an integrated framework that allows for the processes underlying marital change to be clearly revealed and examined. The following theory by John Gottman is more narrowly focused, drawing particular attention to the ways in which marital quality and stability can be eroded.

Gottman's cascade theory of marital dissolution

Gottman's (1993) process theory of a cascade towards marital dissatisfaction and dissolution incorporates both behavioural and social exchange theories. Gottman looked beyond the collection of factors blamed for the sharp increase in rates of marital failure (easier divorce laws, women's financial independence), noting that they do not offer explanations for why some marriages last and others are dissolved. In contrast to theories and advice offered by therapists who have generated their material based on their work with the couples they happen to see in their practice, Gottman's theory is based on scientific research with hundreds of couples over many years.

A core premise of the cascade theory involves conflict, long considered to have only a negative impact on a marriage. In the laboratory, couple interactions are studied intensively over about 20 hours, including a session during which the couple is videotaped discussing an issue that is creating tension between them. Physiological readings are taken (heart rate), behavioural responses coded (facial expressions, gestures, reactions), questionnaires completed and interviews conducted. The couples also rate their own and their spouse's emotions during the conversation (to gauge how well they read their spouse's emotions). Trained raters then code the recorded conversation for a range of emotions such as disgust, contempt, belligerence, and validation. These measures are then correlated with the questionnaire and interview data to uncover the 'hidden emotional dynamics' of the relationship (Gottman 1994: 26).

Based on his research, Gottman (1994: 28) concludes that a 'lasting marriage results from a couple's ability to resolve the conflicts that are inevitable in any relationship'. The key lies in the balance between positive and negative behaviours. Couples whose positive interactions outnumber their negative interactions are known as 'regulated': marital stability is stronger when the ratio of positive to negative behaviours is at least 5:1. Those marriages where negativity prevails are labelled 'non-regulated' and are more likely than regulated ones to be unhappy marriages in which separation and/or divorce are or have been considered (Gottman 1993; Lindahl, Malik and Bradbury 1997).

Not all negative behaviours lead directly to marital distress and dissolution, but four behaviours in particular, known as the 'Four Horsemen of the Apocalypse', have been identified as critical in the process by which a marriage can move towards dissatisfaction and dissolution. Criticism tends to lead to contempt, which in turn leads to defensiveness and finally stonewalling (withdrawal).

Gottman's research has also found evidence for a process of change over time in spouses' perceptions of their relationship that results in a 'distance and isolation' cascade. At some point their spouse's negativity becomes overwhelming, unexpected, and/or intense to the degree that the spouse reaches a level of desperation such that he or she will do anything to stop the behaviour. When this point is reached a perceptual shift occurs in which the feelings of love, respect and safety are replaced by feelings of hurt, sadness, being threatened, fear and anger. Once this perceptual shift has occurred it can be very difficult to view the marriage in any other light and the likelihood of maladaptive attributions that confirm a negative view of the reasons underlying other behaviours is increased.

In a more positive vein, related research suggests that long-married couples are better able to manage their emotions such that, on the whole, they experience less distress and greater marital satisfaction than do younger and middle-aged couples (reported in Carstenson, Graff, Levenson and Gottman 1996). This may be partly because they have learned to soften conflict with affection, and partly because, over time, some conflicts either resolve themselves by disappearing, or Australian Institute of Family Studies Research Paper No. 28, July 2002 6 they lose their power to threaten or arouse strong emotions. The need to resolve every issue may also diminish over time as spouses' priorities and behaviour change in light of approaching old age.

Applying the theories to marital quality and stability

The aspect of marriage that is pivotal to both Karney and Bradbury's and Gottman's theories is conflict management - how couples deal with their differences, how they argue and express themselves both verbally and nonverbally.

Karney and Bradbury's model is wider ranging than Gottman's, incorporating specific assertions about the role of individual characteristics and life events. The methods of investigating both theories stand in stark contrast to the literature that has explored the question of why marriages last. Both adopt quantitative approaches, making measurements largely from direct observation (Gottman) or from questionnaire responses (Karney and Bradbury), and although both are ostensibly concerned with investigating marital breakdown they can both provide rich sources of data to enhance our understanding of how marriages can be long lasting, happy and rewarding for both spouses.

The 'strengths' approach has tended to be investigated using qualitative methods, although neither quantitative or qualitative methods is precluded for either approach. Despite the apparent common sense in doing so, relatively few studies have explicitly set out to uncover the 'secrets' of lasting marital success by going directly to the source - long-married couples themselves.