Interesting about MIL writing to you- definitely reply!
You asked earlier about how I dealt with NC and didn't take it personally. I'm not sure I understood why NC would be personal as the WA being NC isn't personal- it's usually that they have other things going on, or are thinking of themselves, or are distracted/busy. If I'm not in touch with someone I know for a while it's never personl, it just reflects that I have things going on in my own life. So that's how I interpreted NC from my H.....(but I am slightly binary in that sense and usually don't take things personally, even when people think I should!)
Not sure if I'm making sense here, but I think the thing to do is to not think about the NC and focus on your own amazing and excellent life. You made the last contact, so let him come to you. He will eventually (he'll have to because of the houses in any case), and you can take things from there. Patience, patience and a bit more patience.
Hope you're having a good evening. Sorry if I was completely confusing!