Sometimes you just don't feel like "Friending"

On most days I try to be there for everyone and every thing and try very hard to be the helpful friend that my friends need. I make myself available almost all the time. I do pretty much everything asked of me. I even volunteer when I feel my help is needed or wanted.
I have days though, where I just don't feel like being there. And I feel like that's okay. But someone always has a problem with it. Why won't you answer my call? Are you mad at me? Why are you ignoring me? Did I do something? Tell me what's going on. Is everything okay?
Dude.... I just don't feel like friending right now. I'm available about 99% of the time for you to emotionally vomit on me or do you some favor and I honestly don't mind. I enjoy bring there for my friends. Its a bug part of what makes me happy. But don't come at me all crazy when I just feel like being left alone every once in a while and make it all about you. Its annoying.