Honestly don't know where to start this but I need some advice/opinions

So i started dating this girl about 9 months ago & honestly i've never met anyone like her! She's so loving, treats me like a king, loves me and was so easy to open up to, and we've had so much in common!

I was introduced to her mom within the first two weeks of us dating & well all seemed well at first! She was talking very highly of me for very long. However, they're a "spanish" household. I come from a family where sitting down on the couch or being in the other person room is normal, however, she had a lot of conflict with me but would never speak up to me. I asked her to go for a drive one day and it seemed that everything was sorted. Fast forward to about 6 months into my relationship with my girlfriend and more of the same problems happen. The mom felt the need to go through my girlfriend to "tel me the house rules" when even my girlfriend didn't agree or like them. The mom always through in her face and was always very toxic towards her calling her a bunch of names and throwing in the fact that she doesn't pay rent ( my girlfriend is 18 ) There we're also plenty of times i was over and the mom would speak spanish so i wouldn't understand. But it was about things she didn't like me doing.

One day they got into a huge fight at like 2am and the mom kept saying that she feels disrespected & brought up my girlfriend ex boyfriend ( who died a year and a half after they broke up ) and said that she wishes that i was like him. She asks me out to go for dinner wjth my girlfriend and the step dad to "talk things out" She told me that she wanted me to "respect " the house rules, yet some days she's fine wjth me doing things and some days she wasn't. I told her to make things clear to me & told her not to bring up past partners. We both agreed and moved on

Everything was all good until about 3 weeks ago. I took the dog out for the day & had work at 6pm. I got to their house at 5:15 & no one was home. My girlfriend gave me the code to the house to drop off the dog and go on. However, when i put the code in the alarm went off! I knew the code to disarm the safe because the step dad yelled it at me one day when i went to take the dog for a walk and told me how to disarm the code.

The mom called me and asked me how i know the codes & i explained it to her, she then asked me to sit down and talk about it with her and my girlfriend. When we met up to talk she came at me with such aggression and attitude. Disrespecting me saying i had no right to do it, asked me why i didn't put the alarm back on ( which i didn't know how to do & i explained that to her ) and kept going around in circle. She started to disrespect me saying i have no right to do that. i constantly apologized to her and took accountability saying i shouldn't have done it and won't do it going forward, and asked her what she would do. That went no where. my girlfriend and her mom started yelling at each other & i told the mom that "she keeps saying it's her house but your own daughter hates living here and cries to me about how toxic you are here" and wow did she snap. She started disrespecting me more and told me i was never welcomed back here and so on & so fourth.

Now comes the juicy part

I picked up my girlfriend one night as she's a server at a restaurant and ends work late. I picked her up at 12 but we got hungry and decided to get food. Her mom calls her at 1:10am yelling at her to get her ass home. I get in front of the house at 1:30 and the mom comes running down the stairs. She starts banging ( not knocking ) on my window. My girlfriend gets out to go inside and the mom jumps in my car and gets in my face. She starts asking me what type of man i am to have her daughter home this late and starts getting close in my face yelling. IN MY OWN CAR. so i told her "bro get the fuck out of my car" and she got heated that i called her bro. My girlfriend had to pull her out the car and the moms so clumsy she fell and scraped her ankle. She got in my face and started yelling everything in the book. These are most of the things she said I never liked you "White piece of trash multiple times, I have no education, Waste of breath, Never respected me, fuck you, i hate you, broke bitch, can't give my daughter what i give her, You do nothing for her, You did nothing for me, you treat your mom like shit, her ex treated her better, how i'm a pussy, how her daughter made the biggest mistake". I told her i didn't respect her & her step dad got in my face with keys between his knuckles trying to fight me. I don't care for the violence so i stood my ground & said "i can give her what you give her, you rent this house". And she kept saying everything and more. those were most of the things i remember.

Well now even up until last week my girlfriend didn't say hi to her step dad & her mom started an arguement & keeps saying "i don't wanna talk about your little white friend" and brought up her ex again. I was gonna try and message the mom to try to talk maturely, but apparently what i got was only a small portion of how my girlfriends been treated by her, her entire life. I can't even imagine what my girlfriend got. but i guess i'm asking what i should do? My girlfriend stood up for me the whole night and even shoved her mom when she had her hands in fists trying to push me around, and even stood in between me & her step dad cause she knows i would've done something. Obviously there's no plan to end things with my girlfriend, as we are on planning to move out soon, but in terms of her mom, now what ?