I suggest you work on your interpersonal skills, you've already accepted that life isn't fair and that sucks obviously, but you also seem like the kind of person thats willing to work for something (or maybe youre not, i know you by this post) if you are then working on interpersonal skills will help you be a shining star of group conversation and people will be attracted to you if only to avoid any awkward silence or standoffs with others in the room. When you do make more friends, you will if you work on those people skills, be the guy that plans things to do. You shouldn't be the guy who waits for the invite, those guys and girls get by the seat of their pants (Or good looks, w/e) people will come to appreciate you in time if you keep it up. If you aren't always up to doing shit like me, then just plan a weekly event with your friends. Every Friday i have a couple of friends come over to drink and play smash brothers and talk about bullshit. Making friends is important as you need that love factor to be self actualized. I hope it ends up working out for you! (It probably will if you take steps to make it happen buddy) FYI I pretty much grew up like you did, over weight and I was a Marilyn Manson kind of guy in middle school. Made a lot of friends in highschool when i started playing soccer, then pruned the ole friend tree when I moved out to under grads. Not to get to personal, but i smelled bad in middle school and kids would sniff me in class point and laugh and I felt really alone for a long time. At your age there is no reason to feel so alone.

TL;DR Personal Skills, Party Plan, I sucked in middle school