Very confusing situation for me. Please Help.

So I really do apologise this but I need serious guidance. It’s a long one.

So my situation starts off, I was in a relationship for almost 3 years with a girl. We met at quite a young age, (16) and we were at different schools (we also met on tinder..)
I won’t go into too much detail, but we had a very strong connection, and bond from the first 2 years. We both lost our virginities to each other, and everything was a “first” for us.

Fast track to around September last year, and we were having some issues. The biggest one, was that our sexual chemistry was slowly fading and she had stated that she didn’t know if she could commit to one relationship for the rest of her life.. which I sadly understood. All of this was particularly hard, because we were considered “a power couple” and a part from these lack of sexual chemistry issues, we had a perfect relationship.

Although in September last year, the issue was present, but we moved on with our lives, had sex on an off chance and I was very patient and didn’t demand anything, I really thought we could turn all of this around.

We took a holiday, in February this year, with an intention, to have some time away to just do our own thing (and hopefully spark that sexual chemistry). We didn’t do anything sexual on the trip.

Start of uni in March, and we are both at the same uni, (she is very social and extroverted) and she has made a fair amount of friends. One in particular, who lives closer to her than I do, and during the period of starting uni (March 11th – to our break up March 31st) they had met a couple times. She had never done anything, as she is completely loyal and would never cheat.

On the day of our breakup, she explained that the reason we had to breakup, was because she had lost most of that sexual chemistry and it was affecting her mental health and she had stated she wanted to know what was out there. *which I understand*. I asked her about the guy she had been in contact with, and she said ” she found qualities of him attractive”. She still quite clearly wanted to be friends since we shared so much together , and the breakup felt like something that “had to happen”. She couldn’t stay when she had conflicting values.

Fast forward to a week ago, and ive found out that she has really fallen for this guy, and of course it really hurt me as I was confused to what she was doing and how quickly she could move on like that.

We have specified meet ups that we had planned prior to the break up, and so after a week of giving her space, we met up at uni to discuss the tickets to the new Avengers movie we were 100% seeing.

She was very open, and honest and she told me that she had developed feelings for this guy, and she wanted to explore them more. They have spent a lot of time together since our breakup and I feel she just kind of latched onto something because of how upset she was with our breakup. It’s confusing to me as well, because this guy has clear issues that I would never see her going for in a partner.

– she told me has significant depression issues (where as she is so confident and out there)

– he is a virgin at 22 (I thought after our sexual issues she would find someone more experienced)

– not really a career ambition (she is very driven, and I mean he’s starting uni at 22..)

-nothing on social media.. he’s very isolated.

All these factors really hit me and it was very confusing to accept that someone I really considered spending the rest of my life with, had moved on this fast and this quickly.

So upon a depressing return after talking to her that night, I found kevin and Ryan’s articles and they helped me get a sense of clarity and what to do.

I am currently as of writing this 4 days into no contact, and after we spoke, I took the approach of keeping a little thread between us so we would have small talk on Snapchat etc. Both initiating something. But after i found this website. I stopped contact completely.

She seemed confused and snapped me a little bit (at times where she was at this guys house late at night) to which i wouldnt reply. However on the 2nd day of NC, she sent me a whole text asking if I was okay, and how she really wanted to be friends and keep in touch. I replied with a line about wanting to work on myself and heal. (Advice on this website)

She accepted and seemed very ok with all of it, and since then has stayed at this guys house multiple times and we haven’t spoken since her long message..

Anyways, now that everything is up to date, I am scared that she is rushing this whole thing with this guy, and she is trying to put the intimacy from our long years of together, into this thing she has with this guy. (It has been 2 weeks since we broke up. And she has stayed over at his house multiple times (something she would never do before) and I can sadly say that I assume they have had sex and done things that make me sick to think about.

My question is, I know I need to stay strong and work on myself, but we have these set dates lined up, (Avengers and a concert together) – how do I win this girl back and keep her permantenly, and judging from everything I’ve explained – do I have a good chance at bringing this girl back into my life?

P.S it’s really scary to think about, but I’m worried they might get into a relationship before the movie, before I can make a move and try to fix this whole thing.