So this is a very sensitive topic to me considering my relationship with both my biological parents are both almost nonexistent, I just need advice or actual mature adults to please hear me out.

So today I'll be talking about my mother but just know my dad isnt much better himself. My mom and dad havent been together since I was born and its ok it's something i came to terms with & i blame no one. My mom met my stepdad while pregnant with me, & hes been in my life since. He is who I consider my father figure even though we no longer speak. He is whos taken care of me my whole life. My mother got plastic surgery in Columbia almost two going on three years ago, she looks great and is more confident which is cool good for her, but her behavior since then has been so disappointing. First, I am not happy with my body myself and anyone close to me knows this. Before her surgery she'd constantly woo & praise me telling me if she had my body she'd wear whatever she want & be so confident, long story short now i am fat & need to lose weight and whenever i buy clothes online that she likes she suggests i give them to her instead bc "that wont fit you". Second, in the beginning of the pandemic we took a family trip to florida and my long term SERIOUS boyfriend came alone, worst idea ever. She cheated on my stepdad with her childhood boyfriend who lived in Miami, & left my little sisters birthday party early just to do it. Came back days later drunk & then told on herself when no one wanted to talk to her, she picked fights with me that whole trip and bullied me the whole time we were there eventually fighting with my own bf over me. (Step dad knows nothing of this) Around 4-5 Ago she got a new job and was happy about that, her and my SD were going through problems and they just got worse so her getting this good paying job encouraged her to save $ so we could move. (Let me just add that I have my HS diploma and can work and go to college if i could but i cant because i am raising her 9 year old since she works fulltime.) A few months ago she tells me she met this guy and was really excited about it saying they had already been out once or twice. I find out this man is a married man in a similar situation as my mother with kids around my age. He just closed on a beautiful house too, so hes not leaving his wife for her like ever. To make a very long story short somehow my mom started sleeping with this man and having relations with him while still living with my stepdad , so literally not even a month ago she wakes me up and tells me we're moving. Nowhere far actually, closer to my bf. But she got "us" a new apartment so we could start fresh. It hasnt even been a month and shes had her little married boyfriend over 4 times. Before moving in I talked to my stepmom who I am very close with and hoped she made this decision to leave my stepdad for the right reasons. For us to really start fresh and have new beginnings considering everyone was so miserable prior to her leaving since there was no relationship with them anymore. But it turns out I was wrong, she did this for herself. So she can sleep out and get hotels whenever she wants and have him over freely. Exposing my 9 year old sister to a new man and then lying to her like shes dumb saying hes the landlord. It is 6am and she came in my room basically arguing with me bc last night he bought us food and she told me he was staying for dinner and i said here? & she replied "Yes here I have to ask u permission to have company??" I didnt even say anything wrong. She came in my room "As an adult" telling me she doesnt like how I made her feel by questioning her and thats the reason whg she got her own place. And that even her bf asked her if I was mad bc he was here. Obviously I dont feel comfortable seeing a new man in whats supposed to be my home so quickly, so The answer is yes, I was . but i would never say that. all i could do was nod my head and say ok because theres no talking to her considering selfishness runs through her veins. I know this long and I appreciate everyone who read this far but please, give me some advice. Shes out of control and pushing me to the edge. I dont know why she would ever think this behavior is ok or acceptable and im not sure why she'd think bringing a man over not even a month after us moving is okay. You dont even know this man. You havent even been sleeping w him a whole year. Like how is this acceptable? We're not even fully settled in. My room is the only room complete. My mom is acting like one of my friends, not like my mother. I am glad the surgery has her so happy and confident but she's making me so miserable with her behavior. I'm in a more stable relationship than she is. I also have nowhere else to go so please dont tell me to move out, I dont work so I have no $. Thank you in advance if you comment though or even took time out your day to read this.