Just after BD, W told me she had gone on a coffee date with someone from her work. At that time I hadn't come across DB and I didn't know how to react to that. She told me like I was one of her friends.
Fast forward few months and she went to his place for a BBQ. She told me that he is only a friend and she would never ever date him or wants to be with him.
What did I do - I told her that I don't care any more. She can do whatever she wants. Also, that I am not her friend, and that only place our life intersects is being co-parents.
I didn't believe her then and I surely do not believe her now. Unless and until there is absolute remorse and wanting to work on the MR, I wouldn't believe a thing.