I have felt the same as you many times in my life. I also try to be there for poeple whenever i can. I take peoples feelings into consideration like you do, maybe this friend your talking about isnt a true friend. a true friend wouldnt say "i cant always be there for you" I think you deserve better than that. I have a hard time making friends and i'm pretty lonley myself, but im working on building friendships with poeple who seem like they are thoughtful nice poeple. maybe you should do the same. AND you ARE worth the time of day, you deserve to have poeple be there for you, like your there for them. dont waste your time on fair weathered friends, best wishes!! hugs!!