I did it. After waffling all weekend, I finally called Martin and ended things. (he restored my faith that he wasn't a total dillhole when, the day after he texted me at 1:30 am, he called and left a proper message).
It wasn't easy -- we have a good connection, and great chemistry, and I was torn between doing what feels good right now, vs what I want in the long run. This doesn't happen often with me, but logic won. Maybe I'm finally becoming a grown-up?
During this warmer-than-expected talk, he reminded me that during an earlier talk we'd had months ago, he told me that he was not long out of a serious relationship, which was preceded by another long-term relationship -- and thus, wasn't in a place to be serious right now. Oh yes... that. I remembered that, kind of.
He said he understood where I was coming from, but hoped we could still stay friends, and "we'll see what happens" down the road. So that's that. I'm missing him a little, but am still confident that this is for the best.
I'm just really ready to meet someone already who is crazy about me, whom I'm crazy about as well. Sigh.