My friend (let's call her Hannah) had a boyfriend (Tom) a few years ago. Turned out Tom also had had a long term girlfriend! (Let's call her Lucy.)
I found out about Lucy when catching up with an old friend who I hadn't seen for a long time. Somehow it came up that we knew the same person (Tom) as he was a a quite popular musician on our local music scene at the time - and that's how we found out that both of our friends were in a relationship with him!
Hannah had been with Tom for about 6 months when it happened but was heartbroken as was really into him. She broke up with him immediately. Lucy had been with him much longer. She stayed with him.
Over the years, I still saw Tom occasionally and made small talk as although he was an utter swine, he was annoyingly a really nice guy who it was tough to be angry with! I assumed he and Lucy had broken up shortly after Hannah-gate as every time I saw him he was out with girls - the odd girlfriend, other girls who he seemed to be casually dating (kissing / holding hands but not seen again).
Anyway, a while back had a catch up with that same old friend who had caught out Tom the first time, when he was with Hannah, all those years ago.
Turns out Lucy and Tom hadn't broken up after all but had stayed together after the Hannah scandal, got engaged, got married, and had a baby!!!! All those times I'd been seeing him out with other women, and he'd been with poor Lucy the whole time.
She popped up on my social media recently in the 'people you may know section and I couldn't resist a peek. Felt gutted for her. Her profile is one of a blissfully happily married mother and wife. My heart broke for her a little bit.
Once a cheater, always a cheater.