I vaguely enjoy sex with my boyfriend, but thinking about sex repels me and I feel self-revulsion after. I nearly climax, but always pull away before it happens. My boyfriend is 15 years older than me and I wonder if my feelings are to do with an underlying sense of power imbalance, even though I trust him and we act as equals.

The simple and common phases of sex are desire – the feeling of wanting sex; then arousal – where the genitals and other parts of the body respond in preparation for sex; then further sexual thoughts, feelings and actions, which lead to orgasm. There can be interruption or dysfunction at any of these stages. In your case, you are unable to experience the first or last. Revulsion could be the result of past attitudes instilled in you, or of sexual coercion – current or past. Or you may simply not be attracted to your boyfriend. Denying yourself your climax by pushing him away suggests you are unable to allow yourself pleasure for some reason that must be uncovered. Or are you really denying him your orgasm? Are you harbouring resentment – possibly due to your sense that there is an unfair personal contract between you? Underlying anger towards a partner will certainly undermine desire, as well as sexual functioning in general, and must be addressed.

• Pamela Stephenson Connolly is a US-based psychotherapist who specialises in treating sexual disorders.

• If you would like advice from Pamela on sexual matters, send us a brief description of your concerns to private.lives@theguardian.com (please don’t send attachments). Submissions are subject to our terms and conditions: see gu.com/letters-terms

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