It hurts because you love, deeply, and it's ok to hurt. Sounds like this was engineered by your MIL, the sociopath. Take it from its true source.
The family you were close to is still there. We each, I think, have our breaking point. For me, it was that my exh didn't stop our divorce, which could have happened any time in the 120 day waiting period in our state. For you, it seems that this is it. Of course when one hits a breaking point one does just that, breaks a little bit - crying being the natural response. I wish I was close enough to make you a cup of tea and give you a long hug.
You will be ok. You will be better than ok. You and the various members of your exh's family will find a new way to be in each other's lives, and yes, it hurts to let the old way go. Feel the pain, know that the only way through it is to feel it and let it go.
Happy Mother's Day, my dear. You are a champion. Do not forget that.
