Sexual difficulties are often understood as residing within one individual: a lack of desire, a problem with arousal, pain. Yet within a relationship, sex is rarely a solitary event. It is something two people negotiate, co-create and make meaning of together. Contemporary research increasingly reflects this, and the work of clinical psychologist and sexologist Marieke Dewitte at Maastricht University offers a particularly valuable lens.
Sex as an interpersonal process
Dewitte's research is grounded in a dyadic approach: studying both partners together, rather than one person in isolation. Her laboratory and daily diary studies suggest that sexual responses are highly sensitive to relational context. In one experimental study, the presence of a partner influenced how arousal was experienced, and the direction of that influence depended on how satisfied each partner felt in the relationship.
Daily diary research points the same way. Positive mood, perceived warmth from a partner and positive feelings about the relationship were associated with more sexual activity and intimacy, which in turn predicted more positive relational feelings the following day. Sex appears to both reflect and sustain the emotional climate of a relationship. The sex a couple chooses to have, how often and in what form, is therefore shaped less by individual drive than by the quality of connection between them.
The limits of assumption
If sex is co-created, partners depend on reading one another accurately. Dewitte's research suggests this is more difficult than we might expect. In a laboratory study of couples, men frequently misjudged their partner's experience, tending to overestimate her discomfort and underestimate her arousal in a sexual context. Notably, the accuracy of these judgements was linked to relationship satisfaction and to how validated and supported the woman felt.
This has important implications. When partners act on assumptions rather than shared understanding, well-intentioned behaviour can be experienced as pressure, withdrawal or rejection. What is not spoken is often filled in with fear.
Desire, difference and meaning
Differences in sexual desire are among the most common concerns couples bring to therapy. Research by Dewitte and colleagues found that some degree of desire discrepancy was present in almost all of the couples studied, and that its impact was moderated by each partner's attachment orientation. Attachment anxiety was associated with higher desire, while attachment avoidance was associated with lower desire.
This suggests that sexual desire may carry attachment meaning. For one partner, sex may be a source of reassurance and closeness; for another, it may feel demanding or exposing. Without communication, a difference in desire can easily be interpreted as a lack of love or attraction, rather than as two people seeking safety in different ways.
Why communication matters
A substantial body of research supports the link between sexual communication and sexual wellbeing. A meta-analysis of 48 studies found that couples who communicate about sex tend to report better sexual function across desire, arousal and orgasm, with the strongest associations found among married couples. Research with couples experiencing sexual pain further indicates that collaborative communication, approaching difficulties as a shared concern, is associated with better sexual and relational adjustment than patterns of blame or avoidance.
Communication, in this sense, is not only about frankness. It concerns responsiveness: the felt sense that one's partner understands, values and cares for one's needs. It allows partners to make conscious, mutual decisions about the sex they want to have, rather than defaulting to unspoken scripts about how sex should be.
Implications for practice
From a therapeutic perspective, this research supports working with sexual concerns relationally wherever appropriate. This may involve exploring the meaning sex holds for each partner, gently examining assumptions they hold about one another, and supporting a collaborative, curious stance towards difference. Many couples find that sexual difficulties ease when the conversation around sex becomes safer.
It is also important to acknowledge the limits of the evidence. Much of this research has been conducted with heterosexual couples, and further work is needed to understand these dynamics across diverse relationships, identities and cultural contexts.
Ultimately, if sex is something partners create together, it is also something they can reshape together, through open, compassionate and ongoing dialogue.
Monica Chiorascu MBACP
Integrative psychotherapist I Psychosexual and relationship therapy I Sex and porn addiction
Therapy with Monica I hello@therapywithmonica.com I 07895053117