Dealing with different sex drives

I was just hoping to get a little advice on how to handle different sex drives.

My boyfriend has a low sex drive and I have a high one. I'm 22 and he's almost 25 (not too sure if age has to do with it. Someone mentioned that) I initiate sex 98% of the time. I can literally count on my hand how many times he initiated sex. He works full time and has really bad sleep apnea, so he is very tired. I'm a server and work about 10-15 hours less than him, but my work is much more physically demanding than his (he drives or sits in an office) Even after a 10 hour shift, I'm still ready to have sex.

He feels guilty when he says no to sex or that he's not satisfying me. I don't feel satisfied and it hurts a little to always feel rejected by him. I expressed that as well, but it just makes him feel guilty.

It makes me angry that sex with him is almost always planned for when he wants to do it (and it's usually on his off day) I just get tired that any other time I try to have sex, I'm rejected.

I love this man and want to spend the rest of my life with him, so breaking up isn't a solution for me. I was just hoping for a little advice on how to work with his low sex drive.