hmmm, well, the good thing is we know you can do this, 'cause you were doing so well before! I'm sure you are stressed abut the family visit, on top of the house mess, in addition to your h. so, at least recognize that a part of you current stress is not even really him.
OK, so how do you get back to where you were? I guess some impulse control would be a good start! So, when you want to call him, put down the phone, and just think a minute or two. And don't. Same for texting, or email. Just don't. Unless there is something that has to be said, like the kids are in the hospital, just let it go for now. When you feel like blurting out something, stuff a figurative sock in your mouth! Heck go buy a nice pair and stuff a real one in your mouth! The kids will laugh, anyway!
Don't worry about whether you are done, or not even started yet until after the family visit is done, too much going through your head now. Just take it a day, an hour, a minute at a time, and keep breathing.