Having issues with my boyfriend's mother

Me and my bf have been dating for 8 months now. His mom has played a huge role in our relationship, unwanted. She is always interrupting me when I'm talking or when I'm trying to address a problem with her she just walk away as if I wasn't speaking. My boyfriend has a hard time putting her in place because she always pull the crying card and emotional speech. I just sit back while she is doing this because I do not sympathathize with her because she treat me like I do not exsist, only when her son is around. it's hard as is because we are a interracial couple. After a conversation we had about fears and dislikes, she completely offended me. She bought a pink monkey. She told me to go look at the bedroom door, it was hanging on the door handle. I was soo upset. Anyway, I just want her to stop trying to compete with me seems like. Isolating me when me and her son are all together, taking money from his wallet, lieing about money and her job. It's just overwhelming. She even try to stop my bf from seeing me on weekends by making other plans with family not including me when we usually include her or she invite herself. I know she talk about me to her family member because she does it to her other sons gf. When we confront her, she try to cry and make it as if she is trying to be helpful. I love my bf and plan on marrying him but idk what to do about his mother. I wish my bf would stop worrying about how sensitive she is because I'm a sensitive person myself and he do not spare my feelings so how is she any different when it comes to boundaries and what she need to stop doing. My bf is quite blinded because his mom doesn't act the same when he's around. She will act one way then another when he's not around. I want to get things right , right now before anything go any further.