Thanks all for your kind words and thoughts. Rose, in particular, you have some good points.
My dad did mention that tomorrow some old friends will be visiting. They were kind of an aunt and uncle to me when growing up. He suggested skyping when they are there. I think that's a better idea, more of a buffer and my mom will have to at least try to act more normally. If my mom does decide to be a pain, I can talk with them. If the scowling starts I will end the call.
After that, though, I'll probably stick with an occasional e-mail unless they specifically say they want to skype (they probably won't). I was always the one to suggest it in the past.
At least we finalized the house transaction and are transferring the down payment. Then comes the new stress of moving.