I don't know if I should feel guilty or not. If i ask any of my friends they all say no because they're my friends. I need an objective point of view.

Im 23 and this girl is 21. I dated this girl for close to 7 months. She was my first "real girlfriend" and my first love. I date and had sex in the past but nothing serious. She had dated A LOT of guys in the past and slept with triple my number. Just for info. Anyways, the story:

I got really mad at her because during a week a month ago she was doing a lot of things to make me feel bad. Examples, she kicked me out of her house on her birthday before cutting the cake because "i had work the next day and needed sleep", and not giving me an attitude a lot of the time for no reason.

I got really upset and decided to break up with her because of her treating me shitty. Then i started missing her THE NEXT DAY and decided to contact her and apologized and cried and said id change and begged, but she wanted no part of me, she said i broke her heart when i dumped her and she didnt wanna date anyone. I later found out on snapchat she was dating her ex again.

Should I feel bad for breaking her heart?