STBXH walked out last year when I was 36 weeks pregnant. We already had a toddler. I'd had my suspicions about his relationship with a colleague and she then became his 'new' gf. I believe they didn't have full sex but there was an emotional affair going on for a while.
Anyway, year down the line, she's been introduced to the children, seems to be lovely with them, they've just stayed with his mum for a couple of days after Christmas.
Logically I know that it is far far better for my children to happy in her presence and with their dad but it really stings and I'm dwelling far more than I usually would. It's so stupid because I categorically do not want him back but I hate the thought of them doing the 'happy families' stuff with the woman who was callous enough to take up with my husband when I was pregnant (I'm not laying all the blame at her door btw, my ex is just as reprehensible in his actions).
My children are so little they aren't aware of the situation to be choosing sides. Again, this is how it should be. I don't want to make it hard for them because I don't want my children to have divided loyalties but I hate that they've gotten away with this awful behaviour and I have to suck it up!
I just want to see if it gets easier really, I know there's nothing I can do to change it.