Am I wrong for not wanting a relationship with his mother?

He & I have 5 years & 2 kids together. His Mom lived with us for 3 of those years. She is honestly a very devious & vindictive person. She tries to control everything about his life, not because she's a good mother but because she has no life of her own and does this to all of her kids. She's tried to get us split up since we started dating. I am a good mother and I take care of him and our kids very well. She tells their whole side of the family I am a horrible person and a tramp. This is not true at all. I have never cheated on him but she has told him she knows that I have/am. I know she despises me because I refuse to let her control how I raise my family. This led to her "jumping" me with her other daughter in law who tries so hard to get her acceptance. Needless to say she had to move out after that. Now she is even worse with telling lies about me and making our relationship strained because he doesn't want to believe his beloved mother would lie for no good reason (he knows he is just in denial). The easiest way for me to describe his relationship with his mom is to say...he is constantly chasing her love & it's always conditional. I have no problem with him loving her so much, it's his mom. I have no problem with her having a relationship with my kids, as long as she only treats them with love & respect. HOWEVER, I want nothing to do with her......ever. This has kept me from family gatherings numerous times. I can't stand walking into a room with his family knowing I was being talked about. Out of respect for him I don't even attempt to redeem myself to his family to save arguments. He is upset and really wants me & her to get along. Is it wrong of me to not want to try anymore after all these years of humiliation?