I can relate. I have a mother in law who criticises and make one feel belittled. I just make it a point not to go there. The only times I do, is when my husband is with me and it is a larger family gathering, then there are escape valves.
I really try not to let her or other negative people get to me or pull me down. They are not worth the time. Best to avoid them if possible. My biological mom is the sweetest most loving and understanding, unselfish woman ever and we talk by phone several times a week. We can talk about anything. She understands my AF health and I her health. To bad, she lives 3 states away. Cling to those who make you feel good and loose the one who don't.