Let's see....I feel lines 1, 2, 3, 4, 6 (though not on here), 9, 12, 14 to vary degrees, with varying frequencies.
You know what I say to those kinds of feelings (or try to, at least)? I tell them to go screw themselves. If I sit there and listen to them, I'm going to fall into a hole. And in that hole, I'm going to be absolutely convinced that they're all true, and I'm not going to be able to realize that none of them are true (because none of them are). And it comes and it goes. Sometimes it feels worse, sometimes it doesn't. And I try to do things to push them away.
On here, I have felt kinda useless. I'm unable to do anything related to the echoes and stuff (because there are people here who solve them faster, and no echoes are near me), and I don't really talk to any fictionals to any significant degree. So I tried to find something for me to do. First it was the Troper Map, which ended up being ridiculously useful, and then the Reficking Document, which is also a good organizational aid (props to Eli for that). And because of that I feel useful, even though I haven't really done anything big, or anything that leaves a lasting impact.
Like with your editing on the wiki. Sure, it's not really noticeable, but it's still a very important thing to have done. Just because it's not really recognized doesn't mean that it's not vital or hopeless to do (it's a hard thing, because I think we all want our work to stand out, to have people recognize us for the work that we do. Still, that can't always happen, and it not happening does not diminish the value of your work. Unless you work in PR or something, in which case you're failing your job

).
And I can guarantee that nobody here is trying to bully you, or make you feel sad and lonely, or upset, or hopeless, or unloved, or any of those things. We're all trying to have fun here, and nobody wants you to be sad. And if you can't see that, then I am going to pick you up and shove your face into that fact until you do, because nobody should feel that way. NOBODY. You are important to this project, and you will be remembered by us. (Also, you have a better Character Sheet entry than me, so....that's something that you beat someone in!)
On the other hand, just to be careful, if these things aren't necessarily related to the ARG, I'd recommend talking to someone about them. Just an FYI, just-in-case.