This post is just great! I am so happy it is on the forum. I was just experiencing this syndrome myself.
Where i was experiencing it was, I found myself giving to my boyfriend by writing a small paper for him (because he asked) and it was in my educational specialty so i could help. But afterwards, i felt resentful and just pulled away abruptly and suddenly withdrew from him and rushed off to do my own stuff (like a sudden boundary was drawn).
A part of me me feels like I am a nice person for doing it and just thinks "Wow, you are awesome for doing that for the other person!." And then a selfish little "snit" in me (that sounds awfully judgmental) is secretlve and saying, he didn't give me anything in return. It is a really annoying little voice of a child.
I guess in giving it is a balancing test within ourselves...
Thanks to all!