2 year relationship M24 can’t stop thinking that F23 is cheating on me, advice? Thoughts?

Me and my gf have been dating for 2 years now. Everything was good and fine didn’t have any thoughts about her cheating on me until a year and some change ago. Are intimate and sex life has literally went from everyday to nothing at all in the last 6 or more months. She used to want to see me everyday, now she doesn’t like it when I spend more then 2 or 3 nights in a row(she does live with her brother now and wants to respect his privacy and boundaries). I am constantly thinking she is cheating on me. I am insecure, an over-thinker, and have had past relationships cheat on me so it’s hard for me to trust to begin with, but for the first year of us dating I never had a thought about her cheating on me. There’s been a couple instances that really make me think. 6ish months ago she went out with some coworkers and was supposed to be back before 2am she was updating me a little bit. She ended up staying until 4am. They went to a gay bar til 2 then after hung out on the beach until 3:30ish it was a group of them 3-4 girls 1 guy. I told her I can pick her up so she doesn’t have to Uber back but she is insisting on me not picking her up. She says they got an Uber the Uber is taking them to her friend’s house then dropping her off back at her house where I was. We get into a little argument over text about why I can’t pick her up and she gets mad at me for keeping on pushing that I’ll pick her up. I have her location, I see when she gets to her friends house. I told her let me know when you get to your friends and you are on your way here. She says okay. I see they get to her friends house and I see her driving away from there and I try to call her she doesn’t pick up then she turns off her location. When her location turned off she was 18 mins away from home(She got home in 20 mins). I instantly call her frantically and text her asking why she turned her location off, she’s not answering. After a min or 2 She says I’m fine. I tell her I’m freaking out and remind her of my past relationships of people cheating on me and she’s not answering my calls. She says your location sometimes goes off(I had a sim issue with my old phone it would go no sim and my location would get turned off and if I don’t turn off/on my phone it won’t show my location). I sit in my car to wait for her to get home. She gets dropped off a couple houses down. I get out of my car and ask why she was dropped off down the street. She says she knew I would sit in my car and wait for her and I ask about her location and she admits she lied about it just randomly turning off. She said you were making me mad and were stalking my location so I turned it off. Then she tells me I knew you would freak out so I told you it was an Uber when it was really the guy coworker. She says if I wanted to cheat on you I would break up with you. We talk about it more and I eventually say okay fine I’m sorry for overreacting even though she lied to me numerous times and turned off her location. A second time she goes out to a haunted trail thing with her coworkers and she tells me that it’s only her girlfriend and her in the car going there. They eventually go to eat at a place right next to my house and I see that same coworker that dropped her off from the other time get out of the car with them. I text her I want you to be able to tell me anything I won’t blow up or overreact if there’s a guy in the car just tell me. She reassures that there isn’t. Eventually the next night I go over and I tell her what I saw and she said that she didn’t want to tell me because I would freak out and be anxious and think that she is cheating on me with him. I tell her I understand that but I told you I wouldn’t and you are not giving me a chance to show you that I won’t act like that again. She eventually says I’m sorry and I should have told you. She says her friend would tell me if she was cheating on me. I told her no way she is your best friend she wouldn’t tell me that. She says I’ll text her and ask. I told her don’t tell her that you are trying to prove it to me I told her just to ask her friend,”would you tell him if I cheated on him.” Her friend text back saying is everything okay what’s going on. She says everything is fine just answer the question. Her friend says call me. So she calls her and tells me don’t say anything so she doesn’t know your here I say okay. I thought she would put it on speaker so I could hear. She doesn’t and she explains that I’m trying to tell him that would tell him if I cheated on him. Her friend says no I wouldn’t tell him but don’t tell him that I said that tell him that I said yes. Then they proceed to talk about other things I can’t her what her friend is saying but my gf says but I’m not a cheater. Then it’s a whole bunch of yes and no and giggles.(I guess also her friend said she was thrown into the middle of a relationship and that she doesn’t want to go through that again). Once she hangs up the phone I ask her why didn’t you put it on speaker she goes I don’t know, I lay it into her why didn’t you put it on speaker she looks at me like she’s nervous and shrugs her shoulders. I keep asking her that same question and she keeps saying I don’t know and it looks like she is about to cry. She then instantly calls her friend and says he thinks I’m cheating on him tell him that I’m not. Her friend is confused and I didn’t want her friend to think that I thought that so I said no I don’t I just told her that I didn’t believe that you said that you would tell me if she cheated on me. Then I hang up the phone. I ask her why did you freak out like that and she says because you thought I was cheating on you and I didn’t know what to do(usually if I ever asked if she was cheating on me she gets mad and pissed off at me this time it was different). I told her you just told me she wouldn’t tell me if you cheated on me so how would that help anything. She says to me how her friend got thrown in the middle of a relationship and didn’t want that to happen again and my gf had just did that. I look at her she’s upset starts to cry and I ask why are you crying she says because I might have just ruined my friendship with her(but I think she was just saying that and she was crying because she almost got caught) she keeps crying and says that she is a bad girlfriend and a bad friend. She kept saying she’s a bad gf and it seemed like she was about to tell me that she did cheat on me. But she says because I lied to you about a guy not being in the car when he was. I kept asking her why she didn’t put that first call on speaker and what did you not want me to hear. She keeps saying nothing, then says you want to know. Then it was silent for a couple seconds as we are looking into each others eyes. She says,”I didn’t want you to hear from my friend that he went with her to me off.” I told her what do you mean I obviously know that if he rode with you guys to the restaurant he was obviously riding back with you guys to go home. She says oh I didn’t think you knew that. I said that’s obvious and kept asking her did you cheat on me. she keeps saying no as she is crying then she gets up and goes to the bathroom and was in there for like 10 mins. She comes back lays back down in bed and I ask her again tell me if you cheated on me it would be better if you tell me then me finding out later that when she reacts how she usually does when I ask that question, she says no like she is mad and annoyed. She says if you ask me if I cheated on you one more time we’re breaking up. I said okay. At the time I didn’t know what to think I gave her the benefit of the doubt because I don’t have proof or anything but I had this gut feeling that she did cheat on me. Ive been going back and forth since then saying yeah she is cheating on me to no she’s not cheating on me I’m just insecure and over thinking. If we were having sex more and she didnt always reject physical touch like cuddling and get mad at me for slapping her butt or touching her boobs I wouldn’t think she is cheating on me. For that first year of us dating she would let me touch her all the time and we had sex like 2 times a day. She would lay on top of me with her pants down with her face towards my feet and just be in her phone. She would let me just hold on to her boobs while laying in bed. Now it’s none of that and when I ask her about it she says she did those things because she felt like she had to or she would lose me. She says that she doesn’t really like sex and she can live without it(she has been SA’d a couple times). To me it’s just weird how are intimacy just flipped and she says because she has low libido from getting off birth control and that bc she is so busy working 2 jobs and going to school full time(our first year together she only had one job while going to school full time time). I just don’t know anymore, I don’t know what to think. I don’t know if my gut is right or if I’m just insecure. Help me out, what do you guys think?