|dc.description.abstract||Extensive research has shown that psychological well-being is associated with high quality romantic relationships (see reviews by Myers, 1999; Reis, Collins & Berscheid, 2000). However, there are many potential reasons for this association. Drawing on Self-Determination Theory (SDT; Deci & Ryan, 2000), the focus of the current thesis was on fulfillment of individual needs as one psychological mechanism accounting for the link between positive relationships and psychological well-being. An integrated model was tested investigating associations between multiple aspects of romantic relationship quality and well-being while also accounting for other close relationship (friend, family) contributions. It was hypothesised that fulfillment of psychological needs for relatedness, competence and autonomy would mediate associations between romantic relationship quality and well-being. Steady romantic relationships sampled during late adolescence and emerging adulthood (17-30 years) were the focus of this study and developmental differences were expected based on maturity comparisons (i.e. age, relationship length and commitment). Prior to testing this Romantic Relationship Quality and Well-Being Model, a new measure to assess partner contributions to relationship quality was developed in two studies (Study 1 N = 215, Study 2 N = 316). The Partner Behaviours as Social Context (PBSC) measure was founded on SDT and, as expected, had three positive dimensions of warmth, structure, and autonomy support. It also had three negative dimensions of rejection, chaos, and coercion. In a third study, structural equation modelling (SEM) was used to test the Romantic Relationship Quality and Well-Being Model in a large sample of young heterosexual couples (N = 148 couples; ages 17 to 30 years). Romantic relationships were assessed in terms of contributions from both partner and self in the relationship. Partner contributions included specific partner behaviours (PBSC) while self contributions to the relationship were voice with romantic partner, attachment security, and self-differentiation. Multiple reporters were used in this model, with one partner reporting on their behaviours towards the other, and the other partner reporting on self variables and well-being. To avoid violating the non-independence assumption, all analyses were conducted for males separate from females. Two distinct types of well-being, both general well-being and life fulfillment were investigated in separate models. Results showed psychological need satisfaction in the romantic relationship was a positive, strong and unique co-variate with general psychological well-being and life fulfillment when all variables were considered. Findings generally supported need fulfillment as a mediator between partner behaviours and both types of well-being and partial mediator between self contributions and both types of well-being. Unique positive associations were also found between selfdifferentiation and general well-being, and between attachment security and life fulfillment. Thus, results supported satisfaction of needs in the romantic relationship as one mechanism linking romantic relationship quality to well-being, with self variables also providing unique contributions on well-being when all variables were considered. Relationship quality with parents was not uniquely associated with well-being in the final models. Friend quality remained uniquely and positively associated with both general well-being and life fulfillment for females, though not for males. Because the nature of romantic relationships can vary greatly during emerging adulthood, the strength of associations between partner behaviours, need fulfillment in the romantic relationship and well-being were compared for different levels of maturity (based on age, relationship length and commitment). Stronger associations were expected for more mature samples based on these indices. For females, associations between partner behaviours, need fulfillment and well-being tended to be more strongly associated for the older group (21-30 years) compared to younger respondents (17-20 years), and for those more committed to the relationship (≥ 80% commitment) compared to less committed. While partner behaviours and need fulfillment (multiple reporters) were more strongly related for males in longer relationships, some associations within reporter were weaker, contrary to expectation. When more mature and less mature males were compared, the association between need fulfillment and well-being was stronger for males in shorter relationships (< 12 months); when males were younger; and less committed. Findings partially supported expectations for females but not males. While gender differences were not explicitly tested, associations tended to be stronger for females and weaker for males in more mature groups. Overall, partner behaviours, need fulfillment and well-being tended to be consistently, moderately related for more mature males and females, and inconsistently related for their less mature counterparts.
In sum, a new measure of specific romantic partner behaviours and a model of romantic relationship quality and well-being were developed and supported across three studies. The new measure is expected to have utility for both research and clinical settings. Moreover, through assessing multiple relational covariates of well-being, it was clear that psychological need fulfillment in romantic relationships was a strong, consistent and unique component of both general psychological well-being and life fulfillment making need fulfillment an important target for assessment and intervention when working with young couples. Education on important couple behaviours for wellbeing, and better recognition of need fulfillment may be specific targets for relationship education and intervention. These may be particularly important for younger respondents and those new to relationships.||