Sorry for the long hiatus . . . let's get right to it: You have to be absolutely sure, in your heart, that you know there isn't much chance this man is going to surprise you one day and sweep you off your feet. And let's say that happened: Would you want, no, do you really need, you, yourself need, a man who, when under duress, would not seek out your support and lovingkindness, but choose to isolate himself?
There are lots of people around, men and women, who live in little emotional hidey-holes. There are also lots of the other kind of people: The ones who are adept at coaxing those other people out, proving to them it's safe, and thinking that this constitutes a relationship instead of an act of charity; after all, it is a kind thing to do -- offering friendship to someone who isn't able to do it on his/her own.
I have been there. [Oh. Have I. I am a post-doc in coaxing.] Many of us have: There is some evidence a person likes you and may want to have a relationship with you. And boy oh boy, attraction is like walking into the light, isn't it? Almost nothing feels better. [Want a couple of all-expense-paid days at a spa, then a free trip to Paris and a brand new wardrobe? . Ummm, Oh, No . . . I think I’ll stay around during this ice storm in case he calls . . .]
Add that irresistible attraction to loneliness and you have a potent combination and a nice, powerful tug-of-war between the coulds and shoulds. But, Damn! That light is a sneaky thing. It blinds you to all of the reality. It lets you see some of it. And you get really good at manufacturing the rest of it. You ever read a mystery book or see a movie in which the plot skillfully leads you in one direction? And then BOOM! It shows you how wrong you were and just how good you are at building scenarios. [Nice quality in a fiction writer, terrible in a vulnerable, lonely person.]
If, after you have read this, you still want to offer this guy 'friendship,' do it with this in mind: You can make the offer, but you better step back and protect yourself and respect your own need for a full-time, really-there man who will give freely because he loves you and wants to make you happy.