Firstly, you have stood up for yourself. No matter WHAT happens with your W, you have to know you could not have continued to live with such disrespect. You have a tough sitch and took action for you.
Telling her MIL...so that's counter to the rules so to speak, BUT I can understand your impulse to do so. A man/woman can only take so much disrespect. Thing is while I know that had to feel good, it fashions you a victim and is a set back if you have hopes to save your MR. What is done is done, you can't change it, BUT I would second Neffer's admonition to you to be calm, cool and relaxed and keep the family out of it.
How do you act? It would be too fake to pretend life is roses right now, it would also be counter-productive to be hostile. You act as though you are living for YOU and your kids ONLY! You will have to fake it to make it when/if she goes out, but otherwise you are accepting of the reality of your sitch, staying polite, respectful so long as she is polite, respectful to you and you focus on what you need to do for your life. You be a realist, self confident, forward thinking gentlemen what she does is outside of your control/thoughts. Unless and until W's actions show change to you, you are living for you and your kids only.
That's my .02 which I hope helps you some. Praying for you buddy. Other vets I'm sure will chime in with great advice.
