If we can get to the point where it's normal to have sex with a friend, then it would be normal to cuddle and snuggle with that said friend. Cuddling and snuggling doesn't mean that he holds any emotions for you - you're just filling his need at the time.
I can't see why he wouldn't want a hookup to spend the night....a night of cuddling can be quite pleasant. And I'm sure that he has no need to hide his goings-on from his flatmates.
Anyway, I'm sure he's attracted to you - otherwise he wouldn't be having sex with you. But don't confuse sexual attraction with him actually wanting a relationship with you.
Never regret anything that has happened in your life. It cannot be changed, forgotten or undone. So, take it as a lesson learned and move on.