Well, I was initially intimidated by the two pages of crap that landed while I did other stuff, but there was almost zero substance. I'll tackle to stuff I feel worth tackling.
FIX IT, INTERNET
No cando. Honestly, your entire post can be summed up by the following:
I realized i'm in high school and high-school relationships don't really follow much in the way of logic. If i find a specific problem, I'll post it.
This is the answer. There is no accounting for the absolute bullshit that is relationships and stuff at fifteen. Bluntly speaking, fifteen year olds are pretty much never close enough on an emotional level between genders to actually make shit worth of sense when it comes to romantic feelings. Your friend is clearly using you and you are clearly emotionally investing yourself far too deeply into something that is quite clearly a lost cause. What you have is, by definition, a crush. Crushes don't have an expiration date. If you want to maintain a friendship, stop pursuing the guy, as he has made it clear he's not interested in that way. As much as I'd like to say he's unreasonable for the sake of your self esteem, your post (Unless missing MAJOR details) makes it pretty clear that he's not into you in that way. I really can't see anything he's doing wrong. He's not really leading you on, by definition, because he's bluntly told you there's no emotional investment, just random lust. If that's not good enough for you, you need to accept it and move on.
Jens, your problem is clearly self esteem. I didn't honestly read your post, but I already knew this. The hobby shit to shape up is one thing, but another is to practice the hobbies you are already into in a social mindset. The aforementioned photography angle is one that should be mined heavily. Photography is a fantastic way to meet people and a very likable and common hobby. Find ways outside to utilize your photography in a social atmosphere, be it going to the park to take pictures or some such. A camera also makes for a great ice breaker. If you see a pretty girl, asking her if she can take a shot for you while you get in said shot makes for a great icebreaker without coming off as creepy.
Sam, you don't get my advice. If you became any more appealing to the fairer sex, there would be no women left for everyone else. I have to think of the greater good.
Jace, 'only two days?' Seriously, man, welcome to the real world. Most people only really have two nights a week they can go out. In terms of your other situation, well, you're kind of in no man's land. I was actually there in my early twenties. I dropped out of college at twenty and worked night shifts for a long while. It does make meeting women very hard. Honestly, the only way I met women at the time was because I was working at a mall. Since quitting your job to go work at a mall to pick up women is not what I'd call an even remotely viable option, you'll have to be creative. Expand your hobbies, for one. Kung fu does not make much room for women and you honestly come off a bit two dimensional sometimes because, from my perspective, you don't seem to have enough different hobbies. Get heavier into music, as concerts are one of the better places to meet women with your current lifestyle.
Skinnyfat, your situation is hard to justify as anything but your dude fucking up royally. If your dude can't figure out on his own that what he's doing is going to fuck with your emotions, he might be kind of dumb. Conversely, the onus of responsibility in terms of bringing it up is clearly upon you. You absolutely need to tell him it makes you uncomfortable. Whether or not you're being crazy and clingy is less important than the fact you feel upset by this (For the record, there's nothing wrong with being jealous in this situation, I'd be very put off if my girlfriend started hanging out constantly with an old boyfriend who wasn't the father of her kid). The thing, though, is that he cannot be full on expected to right this situation without being told of your discomfort.
This is going to hurt, but I'll be honest. The situation is likely one of two things: either your dude is up to something behind your back or he is too oblivious to the fact that this girl obviously wants to be all up in him again to notice. Much as it sucks, I have to lean toward the former, as it's hard for me to believe there's a dude out there dumb enough to get love poems on his MySpace without putting two and two together and realizing it's time to take a step back.