A few weeks ago, Sabrina* woke up feeling confused and guilty. Despite being in a happy, healthy relationship, she had a wild sex dream about another man. “Before I met my boyfriend, I slept with various guys, two of whom meant a lot to me,” she explained. “The dream was set in a hotel and was about a man who was, like, a combination of them both.”

If you’ve ever woken up from a sex dream with this hazy mix of arousal, confusion and disgust, you’re not alone: Sex dreams account for 8 percent of all adult dreams, according to a 2007 study by the University of Montreal. Sex dreams are perfectly normal, though, and if we look past the awkwardness, they have plenty to teach us about the relationships in our waking lives.

One of the reasons for our sex dreams is simply biology. “The part of our brain that deals with memories, emotions and motivations, the limbic system, is at its most active during REM sleep,” said Yvonne Filler, a psychotherapist based in London. “The limbic system is also linked to feelings of pleasure from sex, so it is very natural