Is it easy for you to walk away from friends once you realize they only use you?

I find I am not as cruel as I once was, and it becomes increasingly difficult to walk away from people even when I know I should. Does it make me the better friend for always being there even knowing they wouldn’t do the same for me? For always being the shoulder yet never having a shoulder? For knowing I’m being used? Or does it make me the fool?

This happens with several “friends”.