DP was in a relationship, the girl had a baby (not his) and he took on the role of stepdad. They were together for 3 years total. They split up in 2019. He continued to see the child every other weekend until mid-2021 when she met someone else. For the entire time she refused to allow him to be stepdad, the child would just know him by his name, eg "I'm going to mark's house".
He hasn't seen the child for around 2 years now.
We split up for the last 10 months but are now back together.
His mother, who is a narcissist and evil as hell (accused me of faking a miscarriage when I lost our son, even though DP was with me) has recently started seeing the ex and the child, inviting them around. She's done this because DP has gone non contact, so it's the only weapon she has left to use. Shes using the child to entice him. The ex will message him saying "we'll be at your mums if you want to see Lucy". His mother has always referred to the child as a brat and said she wished DP would visit without her. In fact, his mother only started seeing the child again at Xmas, conveniently the same time DP went no contact,
Anyway. DP and I discussed 2 years ago what to do next. I encouraged him to either maintain the relationship or leave her life, as to go back and forth does more harm than good. The ex refused to let him see her, so he left her life. The ex didn't try to contact him to see the kid again, until this year when she started seeing his mum.
The child is now 8, he hasnt seen her since she was 6.
I found out he unblocked the ex and she messaged him, (or he started it I don't know) just talking about the child and inviting him to his mum's to see her. He didn't go, but won't tell me much about the conversation, other than to say he told the ex he didn't want to see his mother.
I feel betrayed by this - he has unblocked her and had this conversation behind my back. I have 2 children he didn't bother with for the entire break (because I told him he was no longer in the stepdad role, same as he has NEVER been known as stepdad to Lucy)... I feel like he chose Lucy over my children. I felt like he still cares for Lucy, but not my children.
I guess I'm betrayed he still thinks and cares for that child but not mine, when the relationship has been done since 2019 and he hasn't really been in her life much since.
He doesn't have feelings for the ex, never really did. I'm not worried about that.
His mother has no doubt spread her lies to the ex about me, which also bothers me. I don't know why, I feel like the ex had power over us - like if she messages, he'll reply
AIBU to feel this way?