Aita for blocking my mother in law on social media?

(English is not my first language so translate)

I 24f just blocked my mother in law 52f after she ruined my mother's day. I had a miscarriage 2 weeks ago which I am still struggling with, we only told our parents about this news so they knew about it. Now today while we were with her she had the brilliant idea to ask if I would not tell the news to my sil 31f. Once when we were in the car the tears started to come and my partner called his mother and started asking her if she really had to ask this today, she then said that she did nothing wrong and it was my fault because he was angry with her so I blocked her on everything and now she is texting my partner why I blocked her.

This is certainly not the first time something like this has happened to her. When she is wrong she always blames it on her borderline or autism (I have bpd myself) and she never takes responsibility when she has done something wrong. So aita for blocking her?