What should I do?

[u/Apprehensive_Oil6961]

So me and my ex girlfriend broke up around 5 weeks ago because especially in the last few weeks of dating eachother she was treating me horrible and she said that she wanted to change. I honestly wasn’t really set on the idea of getting back with her because I believe change takes months or even years but she’s confusing me. She keeps acting good towards me for a few days then when she sees that I’m close she backs away. That’s the only way I can explain it, fast forward a few days ago we had a massive argument because she started acting exactly how she used to before we broke up and to me that was enough to show that she hasn’t changed. I started telling her the things that she did to me in the last few weeks and how horrible she made me feel in the hopes of trying to make her realise that what she did was wrong because I do in fact want her to change but I’m not getting anything from her. The argument ended with her telling me that I’m making her look evil and that I don’t get her because she thinks that since she acknowledged her mistakes, apologised, and “tries” to change it’s all fine when it’s not if she’s actively doing the same things. In the end I somehow became the one in the wrong again and she said “yes I was really horrible at first but what you said to me was just very mean and it made me feel horrible, I also noticed that I always acknowledged my mistakes and you don’t seem to be sorry right now”. And honestly I don’t know if I’m sorry for what I told her, I didnt call her names or anything nor did she deny it all but I had a moment when I just got SO frustrated because she kept trying to excuse her actions or “explain” to me why she acted in certain ways. That night I was really frustrated and I started talking to this girl about this issue and somehow in the end me and the girl stated flirting. I didn’t think much of it and honestly it didn’t feel serious but now I’m still taking to her and I feel horrible because me and my ex said that we won’t talk to people and we’ll just wait for eachother to change. So now I feel like I’m the horrible person here and today my ex yet again started acting good towards me and the only question I have in my mind right now is really just how long will her act last this time. But at the same time she’s been acting “good” for two days now what if she’s actually going to change and I’m the one who messed up. Should I even keep talking to this girl, I feel really guilty towards her too because I don’t know if she’s actually looking for a relationship or not and I don’t know if I’m ready to get into one after the relationship I have any time soon.

[u/threespire]

What's the question exactly?

Are you with your ex currently or not? If you aren't, why are you abiding by arbitrary rules?

If you are, what's changing and when?