As a man (sorry I'm not a Mum but I'm realising there's as many men as women on MN), I just had to reply to this, you might even be my (now ex) OH, as this is the sort of thing she would say!
I found your post, and others, quite enlightening about why women might cheat. I think opportunity and ego were probably part of why my OH cheated so much. As for lack of consequences, I think that translates to not giving a shit about the consequences, or that a casual shag here or there was worth the risk. Before we met I did plenty of shagging around, always being sensible enough to take precautions and mindful of the consequences if i didn't. But when I met my OH I was besotted with her from day 1 and despite lots of opportunities continuing to pass my way, and some of them very tempting in the moment, fidelity felt completely natural having previously having been sceptical and quite happily single.
Fast forward 16 years and 2 DC's later, and it turns out she'd been shagging around for much of our relationship, I guess at every 'opportunity' - with colleagues, ONS's, strangers, including (among others) in the back of our car, in a dingy piss stinking car park, even in a strip club ffs. So I guess I must have become that unattractive, impotent man no woman would lust after as one poster responded above. On the other hand, maybe I just loved her so much I couldn't contemplate doing something so hurtful.