Ex bf lover

So I have this ex bf, who now has a gf and a baby.. He came to my great grandmas all night funeral, he got there at 1 in the morning and left at 6, and we caught up on life and how he was and how I was.. One thing led to another and we ended up having sex in the car. 
I don't feel bad.. 
 I'm single. & he still hits me up just for sex which is fine because that's all I really want in my life right now. PLUS! The gf does know about me... It's her decision to stay and that's fine because at this point all I want is just sex.
Is it possible to have casual sex with an ex bf? And not get any feelings?