How can I compete with my ex-gf’s new fling?

I (26M) and my ex (21F) currently live together. We broke up a while ago after I lost control of my anger and verbally abused her over some things that happened earlier in our relationship (cheating, lying, etc). Since then we’ve gotten into many verbal and physical altercations, but we’ve always made it clear that we wanted to stay by each other’s side and have done our best to resolve our issues and build towards fixing things.

That was until maybe a month ago, when we had a dispute over her spending money on weed (I’m fine with it, but at the time she had been unemployed since December and I was mad that she was spending so much on weed instead of food or bills). I was frustrated and essentially decided to tell her that she could no longer rely on me for money, rides, food, basically everything that I was providing for her. I also stopped interacting with her as much, stopped spending time with her at home, started sleeping in a separate room, etc. My hope was that this would have pushed her into being a little more responsible with money and more independent.

Well it pushed her into relying on her friends more, namely one of her male friends, Dylan. Dylan has a car and could take her to work and to the grocery store whenever she needed. Dylan is closer in age to her and is also a creative/artist like her- while I’m more of a boring business oriented person. They began smoking together and spending time with each other frequently so it’s no surprise they developed mutual feelings. When i found this out, it started another argument where I was verbally abusive, and my ex spent a few days in jail after she responded with physical aggression.

Those few days were unbearable for me. I spent hours waiting outside of the jail trying to find out about bail, then even longer waiting for her to be released once it was paid. It took a few days to restore open communication between each other, since we each needed time to process what happened. Once we did start speaking again, my ex told me how she called Dylan from jail instead of me, because she didn’t want to talk to me and didn’t think I’d want to talk to her, and how she was surprised that I came to visit her in jail a few times during those two days. We had a discussion where I expressed that I wanted to fix things, and she said she did too.

I will be seeking therapy to deal with my anger and to process the things she did to me in our past that are causing it. But I know that because I let things get to what is pretty much a point of no return, it’s going to take a lot more than being nice to her again to win her back. Additionally, Dylan has several advantages over me:

-New flings are more exciting, especially when your current partner and you aren’t on good terms.

-He is in better shape physically and has more substantial “intimate structure” and performance (the things you find out going through someone’s phone 😓)

-He is closer in age to my ex

-He has a mutual friend group with her

-They have more shared interests and hobbies than I do

-He is a photographer, my ex is a model

-He has a car, I don’t (by choice since I live in a walkable area and my apartment building has cars residents can borrow on demand). This is an important issue because having a car is what allowed my ex and I to get closer when we first started dating- It gave us the ability to spend more time together in a private/enclosed setting and I guess is also how she and Dylan got close

The areas where I have advantages over him:

-I have an actual job/career where I make more money than him, enough to pay our rent and bills alone. Dylan drives for instacart and doordash

-I deeply care about my ex, to the point where despite being stabbed and bitten by her the previous night, I spent my time and money to visit her in jail to check on her and bail her out once bond was set. Dylan didn’t do any of that, and even if he did care enough to find her case information probably wouldn’t have been able to pay it. We have a long history of me being the only consistent person in her life, always there for her and doing what I can to help her, and I think that can go a long way in her choosing who she can rely on.

-I might not be a photographer, but I have resources and experience that can help her career as a model. I’m supposed be taking her to LA for a shoot with a major brand later this month, which I kind of facilitated as her impromptu manager.

I don’t think he’s objectively more attractive than me, we actually have a similar facial structure, but I probably have 150+ lbs over him, usually have a pretty disheveled look, I don’t know how to dress well (I’m high functioning autistic so it’s hard to feel comfortable in anything that I don’t usually wear like a t shirt and sweats).

She’s told me that their relationship isn’t serious, definitely just a fling, but how can I compete with him more, so that when I show that I am ready to be a better partner again, she won’t hesitate to drop him for me (which would also mean severing their friendship, that’s definitely not something I would allow to continue).

I plan on getting another car soon, building a workout schedule, making healthier choices, etc. Do I need to get a personal stylist? Go out more/try new things to seem more interesting? Try to leverage some of my creative skills more? Let me know your thoughts