loaner to couple: desperately seeking advice

[TsPoet]

I’m 44 and I’ve always been a selfish loner. I started espousing the value of NOT being a couple when I was 12 (or so I’m told), but I really believe that. I honestly believe that coupling up is something that we are sold and it isn’t necessary or even a benefit. I don’t want to be taken care of and I don’t want to take care of anyone else.
I’m hoping there is someone here that has experienced being a loner to being a couple that can tell me how it worked out (especially when they were old and set in their ways). I’ll happily read anyone’s thoughts on how to live with someone else, regardless of their history.
A few years ago I met a guy via bikejournal. He moved to the same town that I live in (coincidence), so we decided to get together for a ride now and again. For the last couple of years we’ve been friends, very recently our relationship changed. We went from casual friends to a whole lot more in a split second. I can’t believe this and I am flummoxed and confused and tired of arguing with myself – break up with him (I don’t want to, I really l,l,l,lo,lo,like him), tell him that I want to continue, but not so seriously (but I really don’t want to lose him), jump off the bridge and try to be a couple (but, the thought of having someone around all the time makes me a little nauseous, and if I fail then I’ll lose him as a friend).
(there are a few on here who know me, and probably know who I’m talking about and I’m hoping they will be very careful about mentioning this post to anyone, even their wonderful DH since we are all active on other bike forums and facebook friends).