Friends with benefits??? Advice please

I've been friends with this guy for over 2 years but we were never that close. The past two months we have been getting closer. Around early February he told me he was interested in me, but I said I wasn't sure and asked him to give me some time to think.

About a week later I told him yes I am also interested but I don't want to rush things and just take it slow. He agreed. A few days later he said he did some thinking and he doesn't think he can afford a relationship yet because he is studying medicine and he wants to focus on his studies this year (it's his last year of uni).

So we agreed to just be friends. I still hang out with him very often, and inevitably since we do like each other we ended up having sex and do it quite regularly too. He was a virgin at 25 and I was his first.

Then he told me that this grey area is confusing him. He doesn't know what we are because we are not dating but we see each other regularly and get intimate. Somehow we agreed that we are just friends with benefits.

This worked well for a few weeks until last week after we had sex he said that he doesn't think casual sex is for him because it always felt like it's something more and we are not just friends. But in front of our friends we act normally as if nothing is going on. He said it doesn't feel like him to have sex with someone who isn't his girlfriend. I respected his decision so we ended it then.

We are still very good friends and last night we were hanging out together. I ended up just chilling with him in his room and somehow we got cozy and were cuddling. Then he said, "One last time wouldn't hurt I guess" and started kissing me. We ended up having sex which is okay with me but after we finished he seemed a bit guilty about it? He said "this shouldn't be happening, i'm sorry but I don't know if I can keep this going"

This has happened several times where he is doubtful and feel bad about it, but he's always the one who initiates. How should I proceed with this? My friend told me maybe I should step in and be initiative to say no so he doesn't regret his decisions if it seemed hard for him to stick with his decision?

What would you do in this situation?