I feel for you. I cant let anyone in for reasons not too dissimilar from your own. I want to be close to someone I like for a change instead of having to settle for who liked me (regardless of what I felt) so consequently I ended up in abusive relationships all my life. I seem to push away anyone who could possibly care for me. how I do it, and why i do it I have no idea, it just happens and leaves me with the same problem IE being liked for their own selfish reasons and tolerating the abuse while they suck me dry till I have nothing left to give, then get discarded without a thought. this has caused me to isolate more and more till I am a virtual shut in with almost no human contact at all.