How do you cope with disappointment?

I'd really like to know.
Recently I've been ignored by two of my closest friends. For reasons I honestly cannot comprehend.
I understand that they have lives, are busy, study, all that jazz. But when I see them online for 4+ hours blogging or browsing DeviantArt, having seen my messages but not responding; what am I supposed to think? I feel like an annoyance, but all I want to do is have a conversation and talk with someone I've known for 5+ years. 
I don't want to come off as needy, all I want is my friendship back. I've tried to shrug it off and continue on with my life, but it's difficult when you know you're being ignored by someone you care deeply about. 

So, how do you all cope with something like this? I'd like to try and deal with it another way.