I can relate to the ex-MIL scenario.

Although I wasnt married to my ex, her mother was a constant thorn in our relationship and constantly competed with me for my exs time and attention.

I think you are doing well, BL. You are a great father to your kids and youre processing things in a healthy way. Eventually, you will burn through your anger and resentment and reach indifference.

Youre going to be just fine, my friend. You have a bright future ahead of you.