I accumulated a few friends like that over the years. Friends in need, when they needed something they were friends. When you needed something they were nowhere to be found even if it was just a half-day's help working. One fine morning I woke up and made a decision. I wasn't the least bit mad or upset in any way, I just decided I was done with toting the spongers in my life.
Wrote off six guys that morning, one of the best things I ever did. I also cut way back on doing favors for anyone. Oddly enough nine out of ten people think that if you do them one favor then you should do them more, not that they should be willing to return the favor if needed.
Pick equals for friends, you'll be a lot happier!
Hu