He's still with her, and I'm moving on...

[BeingMe]

One thing I have discovered in my long life, and going through my particular sitch .... is to not have any expectations of anyone. For you, that includes your H, and your IL's (the supportive ones, and the non-supportive ones). No matter what happens, your H's family will always love him more, because he is their son and brother. That is the reality.

Your MIL may support you now, but if you are D'ed, and your H marries OW, and she has children, then I'm afraid your MIL will have no choice but to accept her, because of the grandchildren.

So, you have to decide if you are done with H, and if you are then you actually have to let go of his family too ... well, to a certain extent anyway. Stick to what you decide, and don't look back. However, if you decide to fight for your M, then haul out all the guns and go for it. And, to do that, one of the things you have to do is stop involving other people (it's not fair to get his family to make a choice between you and him, even if he is the one doing the wrong thing).

Just a thought!