I finally feel like she actually is gone. It's an incredible sense of relief.
I found out later that H thought she was nuts about a month after she moved in. (Less than a month after that, he had decided he needed to move. Getting her out was a real process...) I asked him one day if he was being so defensive about the whole thing because he was defending her...or because was defending his decision. He looked kind of sheepish, and admitted he really was just defending his decision. (And also didn't want to tell me things while it was happening because, well, he didn't want to upset me any more--I was already not handling it well.)
Oh...I also found out xrm told H about some weird little fantasies she was having--of hanging out, going shopping, doing things with MIL. Guess that's why she called her those times. (Did I mention that she called MIL?? MIL never talked to her. Couldn't stand her, actually. )