My BF's mom hates my parents for no reason

Ju
My boyfriend and I have been together almost 3 years. He is 25 and I'm 22. He's my best friend and we have such a special relationship together. We are both more introverted and can be quiet and shy people so we get each other. The only problem is his mom. She's nothing like her son -just the opposite. So I've had a hard time getting along with her bold and intense personality. I recently found out that she thinks my mom is submissive and she called my mom a "pathetic mouse." My mom is the most important person in my life next to my boyfriend so I was so hurt by this. In the past my boyfriend has told his mom that my dad gets angry easily and I guess off of just that detail (because his mom has never asked me once about my parents, what they are like, etc) she thinks she knows everything. She also made a comment to me saying that I'm probably shy because my parents are so horrible to me. Not only does it make me upset that she thinks she can judge my parents but she isolates me by putting my more quiet personality as only being valid because I must have been abused to be so timid. Why on earth would she say these things? My parents are wonderful and especially my mom. Is she just so insecure and has to tear down my parents to make her feel good? I want nothing to do with her after finding this out.