One night I’m a murderer, the next my husband’s having an affair. Why do we have the dreams that we do?

We've stopped believing they're messages from the gods. So what are dreams - and what purpose do they serve? Here's what the science says

When my husband brought me a cup of tea in bed the other morning, I could barely muster a thank you". I was furious that he'd spent the night blatantly cavorting with another woman (a friend of ours, no less).

Never mind that it only happened in a dream. The emotions - betrayal, outrage, rejection - felt real. My next words - I had a dream last night" - echoed what Oscar Wilde is said to have deemed the most frightening sentence in the English language.