I don't think you're useless. I think it might be depression.
I was like that for a while; I was going through the same thing as you (expect my parents were not getting divorced), but everything seemed so 'meh' and I would wonder about life and what was the point on living it. Then I would just feel empty and kind of dead.
Don't worry, girl. Things may seem senseless right now, but give it some time and it will all get better. I hope you're sane.

wow girl, I feel ya XD
when I rp, which i love to do, because I like acting and it's really fun for me, but it's hard when I'm looking at a rp, and people disclude me. Like I know they maybe don't mean to, but I feel like when an admins like "hey, you should come join the group room, i havn't seen you rp for a while" I post something, and then nothing else happens. Also, when like I see my post is first on someones wall, but they don't reply and sometime I think : "I could be doing something productive, but I'm just waiting hours for there reply that doesn't come for a super long time" XD
I feel sometimes really sad when I have nothing else I 1: wanna do, and 2: when I people have there own groups of things to do while I'm kind of stranded XD