Friends of convenince....

I honestly think that some of my friends are really just my friend for their own convenience. I am finding this more and more lately. They call me, they discuss w/me their problems. And then either they stop calling me or if I call them b/c I need a friend they practically ignore me.
I just don't get it, am I not entitled to have problems and seek out my friends when I need a shoulder to cry on or just a hug. I bend over backwards for these people! I listen, I give advice, I support, I cry, I hug, I get very concerned. I don't understand why no one does this for me? Do I not deserve the same consideration????