How long has she been like this? And how old is she? My own mother changed after her menopause. She too was inclined to be unforgiving and expected perfection from those around her and this really came out when she was in her 50s and emotionally she went through a really bad time. Luckily she had a close school friend who talked to her. It helped her relationships with most people, but she still let rip at my father and myself as she knew we would forgive her.
Does your MiL treat you husband and your FiL the same way? (They could hide it). If they get the sharp edge of her tongue it could be a compliment that she includes you in the select circle of those who love her enough to forgive!!
For now it may be best to keep your distance just avoid her until you feel stronger and have had time to assess the situation and talk it calmly through with your DH. Cry off invites to their house and let the boys go alone, and try to avoid asking her to yours.
How to Keep Living at Home Longer
When a political leader lies on their CV - can you trust them?


