How does one not become selfish with no one to focus the gift of self on?
For me its through volunteer work, and being active in the Parish, I make a gift of self to the community as a whole. Of course that may mean some think I'm too busy to meet somone, but anyway! As I said before I also do this for "selfish" reasons because I feel rewarded in giving back, and it gets me out of the house.
From my own experience when you offer to volunteer, your only concern should be learning your limits, and eventually saying "No" (OK I'm still learning that ... maybe not all that well ) because there are so many great organizations that can always use an extra set of hands, and once they get to know you they're likely to say "can you also do this?" or "we think you'd be great for this ... would you consider it?"
I understand your point Dawn, I guess I was saying that sometimes what we think we can bring into a marriage / relationship isn't what's needed, and we find out as we're going through the journey that God has really called us for something else - maybe something else we didn't even realize we could do!