Boy oh boy, I'm stupid... I have to be...

So about 6 months ago me and my ex broke up. We were fighting all the time over the small things, things that don't matter, things that are no reason for a discussion, things that are not things, excuses. And when I say we were fighting, I mean she was screaming and venting and bursting over small things and I was like, "ok, sorry if you don't like this but its no reason to fight".
To sum it up, I got tiered of her screaming at me and even saying that I was not the kind of man she wanted to end her life with. Enough was enough and we ended things.

6 Months latter she starts talking to me, she finished her studies and is starting to work, same profession as I, and started to talk to me about that, things she found out, funny things, stressful things. Before I realized we were talking like we used to when things were fine. I even went to her town and hang out with her and some common friends a few times, I ended up sleeping in her bed, because we were kind of drunk and too tiered to make a clean bed anywhere else. Nothing happened, I kept myself on my side of the bed, she on hers. On the last time she held me for a wile, she though I was sleeping, I was not but I didn't knew what to do honestly, so I did nothing, no point in facing her if I am not ready to face myself.
Damn that night we spent half of the time flirting with each other, stupid alcohol...

It has been 6 months and I still have feelings for her, but that is not enough, no point going back into a relationship if we are going to fight over stupid things every day, that is not the life I want, she said I was not that man she wanted for the rest of her life... Why the hell do I still have feelings for her, why the hell is she trying to get me back

Yo official romancer here. Regardless of your emotions for her, humans forget what people have said to them, but they never forget how someone made them feel. That causes problems two fold for you because:
1: She broke your heart and dumped your ass (I'm assuming the role of a friend here so she was a cunt to have done that)
and 2: She also once made you feel loved.
My recommendation is give up on it, separate ENTIRELY and cut off every single tie possible. You are wasting precious time that should be spent enjoying YOURSELF, improving YOURSELF and making sure YOU are healthy. Don't rack your brain over someone that is willing to abandon you. EVER. From personal experience, relationships don't work out after the first breakup, the friendship is never the same either, it is best for you to forgive and forget entirely so you can live happily again without regret creeping up on your brain; leave the regret for her, don't let her drag you down as well. Seriously man, consider yourself for once. Now I can't make you do anything, and words are associated with deception and opinion so you may not entirely believe me, but believe me, be it a nice girl or a bad girl, they will eventually have a reason to leave you. (It takes a very special person to stay with you forever) That's not a cause for upset, please believe in yourself and your own happiness, don't look for happiness in the outside world because believe me, it begins from within. Once you have learned how to handle situations that threaten your mental and emotional health, you can begin to trust, but it's better to not have trust at all than to have it broken. Have a happy Valentines Day bro, stay lifted! Ja na!