What do I do now?

I ended my relationship with my girlfriend (now ex-girlfriend) of over a year and a half just under a week ago. The reasoning was that the dynamic of the relationship changed for worse since we both went to separate universities. We both agreed it was the best thing to do, and she heavily pushed the idea that we continued talking as close friends with the view to possibly get back together in the future if I adjust to the new dynamic. Of course, I never contemplated this idea and just wanted out of the relationship and the freedom to do what I wanted.

A few days later, I pull a girl in the club and it ended up on my Instagram story. She gets pissed off as I agreed I wouldn’t rub it in her face when I eventually get with someone else.

Last night, she told me she was going clubbing and I predicted (and told her) she would definitely get with someone at the club to which she says ‘she wouldn’t go looking for it but she doesn’t know’.

Later that night she texts me saying she got with this guy she walks to her lectures with, and I said ‘cool’. Directly after this I had a bad feeling she would do more than just ‘get with him’.

No surprise she tells me this morning she went back to that guys house and did everything except for fuck. I didn’t think she had it in her. I’m not mad at the guy but hurt. If she left it at getting with him, we would be ‘even’ of sorts. But she went above and beyond. I don’t think I would be able to do more than get off with a girl at this stage yet she did more than that.

What do I do now? I’m thinking I should cut her out of my life completely. Im not a cuck.

Be brutally honest with your comments. Appreciated.