"I called her a worse name and told her SHE was the one breaking this family apart."
It will happen. These are the moments you have to prepare for.. I know it is really.. really hard.
You need to address this name calling somehow. You need to let her know that you did not mean what you said. That you over reacted. Address it at counseling.. or the next time you see her face to face. Don't text it.. it sends the wrong message. If she is on the phone with you that would be ok to. Simple words.. and don't mention anything she did. Don't use the word "you" at all. Just I and me! Holding yourself accountable.. teaches others what you expect.
"So..the day ended horribly and they are both headed to New England. I'm headed up on Friday. We have agreed that we will NOT discuss the R the next time we meet."
Good Plan! Right now.. just ride the wave my friend. That is all you can do.
"The problem is that within 60 days I am going to have to make some decisions and her decisions will drive mine. Maybe that's the problem...maybe I should just do what's right for me???"
60 days is plenty of time. Don't go all "crazy" with your decisions. Write them down.. or post them in order of importance and address them one at a time. Think about your options.. is there a better way?
KISS it.
"I did NOT keep my emotions in check. That's my biggest challenge...that's the "work" I have GOT to do if this is going to be salvaged."
Now you "see". Trust me that will make you feel like you are Doing Work.
Relax Eat Think Act normal React.. Smartly. Do something different. Emulate. Do Work.