So there's a stupid storyline on a soap that DH and I watch (soaps are on in primetime in the UK) where the village vicar and his wife are having marital problems. The wife nearly left her husband for another man, but didn't at the last minute. The wife was telling her friend about it and said "I had an affair."
Now, this is where I need your help.
The wife and the other man never slept together. They certainly had an emotional affair and there was definitely a betrayal, but when she told her friend "I had an affair" my first reaction was "but they never slept together".

So, if a friend said to you "I had an affair", with no other elaboration, would you assume that means they had sex with someone other than their SO?