<human>: Could you distill the essence of the text into 1-3 sentences?

2 years ago i had a lovely girlfriend and she broke up with me after 4 months because she thought that I was going to break up with her and she wanted to be the first one to do it. 

I wasn't actually going to do anything i was just beginning to settle into the relationship.
The whole situation is kind of fishy so I don't know if there was anything else happening. But I'm not too bothered tbh.

Anyway we've been going to the same parties and gatherings more often and since about 1 month ago, shes being trying to hit on me and
kiss me. I've been turning her down but about a week ago we were at this house gathering and we ended up kissing. 
I didn't feel bad or anything, i didn't know what to feel.

3 nights ago we had sex and it was really good. 
Although at the moment I'm kinda confused...

Do i carry on doing this or do I tell her enough is enough.
I don't want to get back into anything serious with her.
<bot>: Old ex gf, we are getting back together, I don't wanna get into anything serious, but I don't wanna hurt her. What do i do?