New research shows there may be hope for the relationships of the depressed

Your closest relationship should be the one that offers you the most support by providing you with emotional gratification. For people who experience significant symptoms of depression, that support would seem particularly important. In the best of cases, your sad mood and low self-esteem could be offset by a partner who allows you to feel good about yourself and helps propel you back to an emotional even keel.

Over time, that continued emotional buffer against the world could perhaps help to reverse even your darkest moods. Your depression may ease as your partner provides a stable base of love and affection. By the same token, a chronically miserable relationship could lead you to feel despondent and hopeless. Although you began your relationship with an optimistic and hopeful frame of mind, you’ve grown instead to feel that your life is doomed by the mistake you made in committing to remaining with this individual over the long 

These scenarios raise the thorny theoretical issue of cause and effect when it comes to long-term relationships and depressioneople who are depressed can be made better or worse by their relationships, to be sure, but can’t a poor relationship create its own source of depression? Furthermore, if one partner is depressed, might the ensuing conflict and unhappiness create a similar despondency in the other partner? Translating the theoretical problem into the research needed to evaluate causality would seem to be almost impossible.

Fortunately, some possible answers emergency  from a comprehensive review of the available literature on married couples by the University of Quebec’s Maria Goldfarb and Gilles Trudel (2019). Many studies on the depression-relationship quality link take a cross-sectional approach that produces correlations on a single occasion. These studies by themselves don't allow causal connections to be discerned.

However, there are some investigations that follow couples over time, making it possible to determine if the depressed have worse outcomes in their relationships than the non-depressed. Indeed, the most sophisticated approaches trace bi-directional patterns, determining whether depression at Time 1 affects relationship quality at Time 2, and vice versa. Furthermore, as Goldfarb and Trudel were able to uncover, studies that examined these patterns in older adults provide even better answers to the causality question. Taken together, cross-sectional and long-term (longitudinal) studies, involving younger and older couples, make it possible to start to see patterns in the depression-relationship quality connections.