Hi Sage, I'm sorry to read how this is playing out, and how he is swinging wildly between wanting to be your BFF and next thing giving you a full-blown character assassination.
Do you really think your MIL said that about you? Chances are she didn't, or chances are that she responded to some fabrication of his, and was not reflecting on you at all. If MIL has dealt with a broken M herself (which I think I read on your MLC thread?) then I would go as far to say that she knows that there are two sides to every marriage breakup story.
H sounds like he is terribly confused and still needs to convince himself that he is doing the right thing. He left because he blamed you for making him unhappy. And he has left and is still unhappy....he will continue to find some way to blame you for making him unhappy. He will continue to convince himself that you are unreasonable, abusive, because that is all he has to cling on to for his rationale for leaving you. Well done for going NC - that too probably made him angry! Don't take it personally Sage, don't let him drag you down with him. x
M:49 H:49 T:20 M:18 D:16 D:14
EA: Feb 2019-May 2020 Separated: Mar-early Aug 2020 H asked to reconcile: Jun 2020 EA relapse: Oct/Nov 2020 Recon #2: since Nov 2020