Well, of course I don't know the whole story but from what I am getting, it sounds like Nathan does want to be your friend, it's just that the issues you are presenting him with are a lot for him to handle. Our issues (I'm talking about most of us here on PC) are a lot for anyone to handle.

I had (I say "had" because I lost this friend recently due to my own actions) a very good friend who told me he didn't want to be my emotional support. This didn't mean that we weren't very close and didn't hang out and talk all the time. He just wasn't the person who was going to be my support when the world was crashing down; he didn't want to be that person for anyone, not just me. Some people can't handle that, and it isn't fair--when they express that boundary--to expect them to be that person for you. Unfortunately for me, I had a bad period of time where I was off my meds and going downhill and I laid that all on my friend and he pulled away. The more he pulled away, the more I leaned on him and our friendship broke. You don't sound like you're in that place--Nathan still wants to hang out with you. I think you should allow him to have his boundaries! Accept them and be happy with this friendship...he's right: don't push what you have away.