My (24ftm) partner (21m) doesn't really have a sex drive anymore, and im having a hard time navigating conversations about it

Hes my best friend, I fell in love on our first date and we haven't had much ups and downs, just growing and learning as young adults do. We've been together 2 years, and when we first started dating we were long distance for about 7 months before we moved in together. At first, we would see eachother once a month and would have sex as much as we could during our visits. Then after we moved in together we had a fairly vigorous and healthy sex life, probably 3-6 times a week

This slowed down over time, and my partner went into a pretty bad depression slump about 9 months ago that he's only just starting to come back out of. Ive done everything I can to alleviate pressure on him, and he's doing so much better than before, but one thing that still hasn't come back is his sex drive. The way he describes it, he doesn't think about sex independently, doesn't masterbate, doesnt watch porn.

He will still have sex if I initiate most of the time, and has told me that he enjoys sex once we get started, just that he doesn't think about it on his own. As it stands, we has a scheduled kink night once a week for our kink/intimacy and one-on-one needs, and I initiate sex once every week or two. I usually just do things to him though, and he cums really fast. Like 5 minutes or less, and its really easy, and I've always enjoyed it, but it means I don't get off. It takes me anywhere from 10-15 minutes of just the right thing to get there, and while he days hes happy to do it, after a few minutes I feel intensely guilty that hes not also getting pleasure and it ruins the whole thing for me. It was getting better for a while, but since his sex drive disappeared I feel even worse and most of the time I can't even bring myself to ask him for any kind of reciprocation at all.

We've talked about it a few times, hes very insightful and knows me really well, and every time has said that he feels immensely guilty because he knows I'm probably really struggling with feeling desired sexually and can tell its affecting me. During talks before though when hes said this, one time I agreed and he said he feels even more guilty and got really upset. The next time, i deny it, I said everything is okay, and he gets upset that im lying to him. The last time I just went with what i thought was best which is that its my fault we don't have sex more since I dont initiate like we've discussed. I told him I was struggling with initiating and with asking him for pleasure, and his answer was basically "just ask!" Which isn't really helpful, especially with asking for pleasure because it feels like hes only doing it because I asked him to (because he is)

How do I talk to him about this without making him feel even more guilty? The longer we go with such a one-sided sex life, the worse i feel and the harder it gets to talk about.

TLDR; BF has no sex drive and feels guilty about it, I dont know how to initiate or how to navigate conversations about it without lying to spare his feelings.

I dont know, any help would be greatly appreciated.