My mom and my boyfriend have been getting too close and she is much nicer to him than she is to me. She's been giving him money, paying to fix his car, giving him rides to work, picking him up, etc. And I feel as though it's all because he has a job and I don't. He has been physically abusive in the past which I never shared with my mom because I thought she would react badly and not allow him to live with us (we rent out the granny flat). I called the cops on him new years Eve because he had choked me once again and I was afraid he was going to kill me eventually if he continued doing things like that. I came to find out that my boyfriend asked my mom if she could give him a ride to court, and he told her why (he needs to get an extension for domestic violence classes). So now my mom knows that there's been domestic abuse going on in our relationship. She didn't say one word about it to me! We were texting and she told me she was going to give him a ride to the courthouse, but that was the extent of it. Not only that but she offered to go in with him (for support I assume). I am beyond hurt by this. Not only does she not care that I've been abused by him but she is supporting him through it all! It literally makes me sick and not want a relationship with her. The both of them have narcissistic traits and are toxic, but that doesn't make this all hurt any less. I feel like she is "on his side" for lack of a better way to put it. She did something similar with an ex boyfriend of mine many years ago as well. I don't understand why. Is she doing this to hurt me? Why would she want to be there for an emotionally support a man who has abused her daughter and gotten arrested for it! He was charged with domestic assault with bodily injury which is a felony because he choked me.
Domestic abuse victims are 10 times more likely to be killed if the suspects choked them in the past!

Can anyone tell me why she might be doing this or why she's like this? I never thought she'd do such a thing, even as cold and toxic a mother she is. I've struggled with feeling unloved by her for a long time, but this has truly broken me.