Definitely be his friend, making friendship the basis of your relationship is never a bad thing. But in the same breath, I suggest not to completely shut any doors for something more. By that I mean, don't go too cold on him, it may make him withdraw more instead of refocus toward friendship. If you can accept the space he's in today, and maybe a different space he's in tomorrow,(example today i just wanna hangout and enjoy your company, yet tomorrow I feel the need for a little extra, like a cuddle and a movie) it will reassure him that you accept him and what he's going through.

Yes sex definitely complicates things, so its up to you how and where you draw the line in the sand of friendship. Me, it was ok to be intimate, without a commitment because i knew he loved and respected me.

Note i said "ok" not "easy" hehe. I had some issues with it at certain points definitely.

This is not to be confused with running everytime he calls or letting him walk over you though. I know I never needed to worry about that with my bf, because of how well I already knew him, but it can be an obvious risk with someone you don't know too well. They can take it to mean you'll "take anything"...

Sorry idk if I'm being all that clear, but wanted to respond since you requested more feedback.