Seems the ones who push the hardest are the ones with the biggest problems, both drinking and other problems.
I had a pretty annoying mother. I finally got to the point that I would just totally ignore her when she started pushing buttons. I mean, she was in her fifties and had been the same ever since I knew her so she wasn't likely to suddenly change.
If she got too bad, I would say, "Mom. I'm not having this discussion." Then I would walk away or hang up the phone. I mean, if she wanted to pout, then by all means pout without me being your witness. Controlly Controllerson Moms are pretty common.
Good luck with MIL. Just look at her when she "starts" and don't engage! It worked for me. She'd be over there being all upset and I'd be on to something else. Talking to someone else.