I don't understand infidelity, well I do, but I don't. If you don't want to be with someone don't be with them.
However I'm not naive, I've cheated and been cheated on. Neither nice nor productive. But the two incidents I feel most guilty about are the two where the men involved had girlfriends *gasp*.
The first time
We worked together, he had flirted with me from day one, a few weeks after he started he and his girlfriend broke up, the next six weeks involved him asking me out. I declined, going out with someone from work is one (bad) thing, going out with someone at work who had just broken up with his girlfriend is another (bad) thing. After about three months we went out for dinner, drinks - cut to an expensive (for the area) hotel. We started seeing each other, if we didn't see each other at night, we would meet for breakfast before work. I was at his one night and I found a (positive) pregnancy test in the en-suite bathroom, he said it wasn't his, no shit Sherlock, unless he had grown a womb overnight and it certainly wasn't mine. It turned out that he hadn't broken up with his ex, but she had been looking after her sick mother for the past few months. I have never felt so sick. I left immediately and spent forty pounds on getting a taxi home.
She thought something was amiss and spent the next couple of months calling me without speaking. I wish I had had the bollocks to have forgotten my shame and actually explained to her what a deceitful person the father of her child was. But I didn't have the courage.
The second time
More recently. In fact probably about seven hours and twenty minutes after I proclaimed I would stop shitting on my own doorstep and in walks my long term crush. I met him about three years ago, I fancied him and was in awe to the point that it took three parties before I casually asked someone else who he was. 'Sex on Legs' with the right amount of caring and arrogance.
A group of us are drinking, playing drinking games, it ends up with just us, drinking and playing. The next forfeit was a 100ml shot of cheap vodka, so cheap it wouldn't freeze, cheap. I downed it, only for it to come straight back up. How we end up kissing after the vodka in mouth, out mouth, on floor, kitchen towel mop up, I'm not sure. But we did kiss, snog, pet, shag. About seven times between three and six in the morning. I was hungry for every part of him and vice versa I guess as he kissed, licked and bit most of me.
The next morning I was very disgusted with myself. I called my best friend and told her what had happened, she tried to assure me that I wasn't guilty of anything as I wasn't the one in a relationship, but I wouldn't let myself off the hook as easily.
It gets worse. I have met his girlfriend and they will probably get married in the next twelve months.
If I could turn back the clock I would do.