Without going into much detail, here is a brief outline.
DH had an altercation with someone, this someone was my then bf boyfriend.
My mf then fell out with me, but, dh is still having chats with her etc, but, she ignores me.
AIBU to expect he sticks up for me and doesn't talk to her a, because he caused fall out in first place, b, I don't like the fact that he talks to her behind me back etc.