I'd like to offer up a different perspective on this.
In my first marriage, I had a few affairs. It's so easy to say that I must have been a terrible person. I'm not. I was totally broken.
I met ExH when I was 16. Started dating him at 17. Married him at 20. I was totally faithful to him, and he was the only man I had ever been with. When I was 33, I found out that for our entire relationship, he had been sleeping with other women - at least 10 women that I knew of, and I suspect a few more.
I decided to forgive him, as we had small children by then, but he carried on hitting on other women, even more obviously than before! Looking back, I think I had an emotional breakdown. The lies and gaslighting, struggling to bring up my children, I felt like I was wading through treacle, trying to keep it all together. He tried to sleep with all of my friends. He did sleep with my best friend in the world (no longer a friend!) He tried it on with my mum, my sister....no-one was immune from his sexual advances. He was also violent on occasion.
Anyway, fast forward another 4 years (so, 37 years old now) and I was in a bar with friends, and I got chatted up by a very handsome guy. At the end of the night, he moved in to kiss me. And I let him. Because what the hell was there left to be broken?
I went on after that to have a few affairs, whilst planning an exit strategy. And I don't feel guilty at all. But....I think women who have affairs are generally a bit "broken", but the men, hmm, not so much. I think they can separate sex and love far more easily. I know now, that I was utterly broken and not of sound mind at that time. And tbh, the affairs don't really help. Well, they help you see that you can enjoy the company of another guy. But invariably they break you further, because these men can't commit and you get hurt, which compounds the awful emotional state that you are in.
I am now re-married and I will never cheat on DH. I am emotionally stable again and in love with him.
I hate it when people say "once a cheat, always a cheat". It's actually not in my nature to cheat at all. I'm a home body. I want monogamy.
People don't realise what sometimes drives a person to cheat. What they've been through.
2 of my friends have had affairs. They were definitely at an emotional rock bottom, verging on full breakdown at the time.