<human>: we went through kind of a rough breakup, we both have mental illnesses and honestly were not healthy for each other, about 3 or 4 days after we broke up she asked for me back and i said no, which is one of the hardest things ive ever had to do.

after a few weeks we were texting one day (she was drunk, i was high) and it ended up in us having casual sex for a few weeks. we established that although it was just casual sex, we both still had clear feelings for the other person (GREAT IDEA, RIGHT??? CANT THINK OF ANY WAY THIS WILL END BADLY)

at the start i just missed her and everything reminded me of her. i've been using drugs music and self harm as outlets and it works but not for very long. some girl kissed me on halloween at a party but i just felt guilty about it. about a week after that happened, my ex texts me being mad about that and i decided i dont want to do the casual sex thing any more because it is obviously unhealthy for both of us.

i went back into a cycle of missing her/physical contact so i tried talking to other girls. i hooked up with one and while it was fun at the time, i just feel sad now because it wasn't *the same*

it's only been about 1 and a half months since we broke up but i just dont know what to fucking do

Can you summarize the given text in a few sentences?
<bot>: girlfriend of 2 years and i broke up -> started having sex because we're stupid -> stopped having sex -> i have no idea how to get over her