Relationship Advice

So will try to keep this vague and somewhat short, but I (27,M) met a girl (23,F) last year that I was casual friends with. At some point or another she found herself freshly single from a longtime toxic ex, and we ended up talking after a few drinks and decided to give things a go between us. I was clear my ultimate goal was a relationship, she wasn't sure, so it was mostly FWB testing the waters. We progressed very quickly to the point where she seemed to be genuinely on the precipice of making something real happen, and her friends were even pushing her to go for it. And then she just suddenly ended it and said she felt nothing for me out of the blue one day. Completely tore down what happened between us and had a million and one reasons for why that she never brought up once before.

I was heartbroken for months while she was off kissing other guys within a week. We never cut contact though and ultimately ended up going back to just friends after a few rocky patches. I've been mostly focusing on myself while she's been off chasing guys that are either non-commital or barely giving her the time of day. We've talked about things a fair bit, and she's kinda changed her tone that I didn't really do anything wrong, and in a lot of ways I was the best she's ever had regarding how I treated her. But she's still adamant that she wants nothing to do with me like that anymore and feels nothing for me.

Thing is, every once in a blue moon when we're both drunk and hanging out, she suddenly gets slightly flirty or minorly physical with me again in a way that feels more intimate than just a friend. I don't let her take things far in order to respect boundaries she set in the past, but every time I ask about what that was about, she has some excuse for it. But the second I do anything that can be perceived as the same, no matter how minor, she's at my throat accusing me of still having feelings for her and threatening to not talk to me anymore if I do.

I can be a bit of an anxious overthinker so I don't entirely trust myself to make the right call if there's more going on here, but it feels like there is, and I can't shake that. But I also don't have the slightest clue how to approach this regardless of if there is or not.

Edit: Something minor that just happened I may be reading into I just remembered. We hung out a month ago at my place and she gave me one of her shirts that fit me, so I offered to give her one of my hoodies that I just suddenly found her wearing all weekend in return. She scoffed at that and said you only do that when you're dating. Well, we hung out again recently and she spent all weekend wearing a different favorite hoodie of mine. As I was taking her home, she swapped back to that same one from last time, and I realized afterwards that she forgot to give it back. I didn't say anything, but did mention her leaving some stuff at my place to kind of prod her. She said she didn't care about leaving stuff there, and didn't even try to bring up that she has that hoodie. I don't think she knows that I know she has it. Almost like she's hoping I forget so she can keep it without me knowing. Maybe that means something. Maybe not. I don't know. Help.