1. I don't think it's an either/or proposition. If, according to you, she knows it upsets you, why bring that up again. Unless you are going to have a consequence that you will follow up on.

It reminds me of that joke about what do British police say to criminals, since they don't carry guns. "Stop, or I'll say 'stop' again."

If you make empty threats then it just become manipulative and in effective.

But DON'T bring it up unless you are pepared to follow through

She's acting like a child. Treat her like one. She starts to spew. Just leave to room and say "talk to me when you can be civil." Then leave and ignore her untill she is civil.

She's texting OM. Give her a consequence. Something like taking her phone off the plan. If she tells you you are being controlling, just say it is not my intent to tell you what to do but I'm not paying for it.

Stuff like that

Of course the ultimate consequence is to file if things are so toxic between you. But you have to be prepared to do it and have to accept it.

Patience is bitter, but its fruit is sweet.
--Jean Jacques Rousseau.