Man breaks up with his girlfriend and she went clubbing with her ex, 'this is crossing a line.' AITA?

"AITA for breaking up with my girlfriend after she went clubbing with her ex?"

My girlfriend (19f) and I (22m) have only been dating for about three months. She had jumped into our relationship quite quickly after her last one which she was in for about a year (a couple of days after they broke up). This has been a big stressor in our relationship, as I believe you need time after leaving someone to heal and reflect.

She told me the relationship died months before they broke up and she just stayed too long. I believe her because I trust her. Due to this, I told her at the start that she must prove to me that there really isn’t any love left for this guy. I mentioned not staying in contact with him and avoiding functions that he would be at.

Last night was her roommate's 21st birthday. At Florida State (the college we attend) it’s tradition to get thrown in the fountain on your 21st, and a lot of people treat it like a big deal. All of your friends show up and support you and cheer you on for finally being able to drink legally.

The issue is that her roommate's boyfriend is best friends with her ex, and they all shared the same friend group while they were together. She told me that her roommate said that I probably shouldn’t come, as it would be awkward for her to bring her new boyfriend around that group of friends who she previously met through her ex and she agreed.

This was the red flag. Why not show off your new boyfriend? She told me that this was important to her, that I shouldn’t come, and that she would hang out with her, see her old friends, go to this fountain throwing and then come and spend the night with me. I was fine with this. The ex didn’t even end up attending that part.

She ended up ditching me to go out to the after party at one of the local clubs. When she told me this was her plan, I voiced my discomfort. She was going out with her ex's friends who specifically said i shouldn’t be around. She had no clue if her ex was showing up. I told her it’s wrong to put herself in that situation especially after all we’ve talked about.

Her ex showed up (with his new girlfriend) and they were all hanging out together. She didn’t cheat on me or do anything like that, but she completely disregarded my feelings and overstepped my boundaries.

Before she got to the club, I called her and said that this is crossing the line we put in place at the start of our relationship, and her choosing to do this shows me that she isn’t willing to sever ties with her ex. So, I told her that we’re done. Being drunk at a club with your ex is unacceptable behavior when you’re in a relationship in my opinion. AITA?

Here's what top commenters had to say about this one:

Spoedi-Probes said:

NTA. You were the place marker just in case this very scenario played out. If the ex was single your ex would be heading straight to him to try to rekindle what they had. It didn't go that way so she had you as the back-up. Do not be the first reserve bf, you deserve more than that.

worthy_usable said:

NTA. She had a clue that the ex might show up. Sounds like this group is too close for her to not have known something. You dodged a bullet.

Fun_Concentrate_7844 said:

NTA. Someone with a spine is refreshing.

marv115 said:

NTA. When she put the comfort of the ex before yours by telling you couldn't go that's more than reason enough to be done.

cosx13 said:

NTA she sounds like a terrible person for multiple reasons and going clubbing with her ex was the final straw. You were probably just a place holder for her.

RatedNforNick said:

NTA at all. You set boundaries that, if she disagreed with, she could have argued in the beginning. Instead, she agreed to them, and then took it upon herself to violate said terms in a disrespectful fashion. Your feelings are justified.

machinezed said:

NTA I would be pissed. She ditched you in the off chance he would show up. When he wasn’t there at the fountain tossing, you still weren’t there. When they went to the bar and He showed up with his new girlfriend you were not told to got to the bar.

You would have made the group dynamic uncomfortable, but the exes new girlfriend is ok. And after that you still were not invited, when he shows up. You are the rebound and probably not worth sticking around.

Mountain_Cloud_6465 said:

NTA, you did the right thing. She made her choice, and you made yours. You were the backup, and this kind of behavior would only continue.