I had to register just to point out how dead-on accurate you are.
I was never bullied either because I became an expert at never being noticed. Camouflage is a fine defense mechanism if you're an octopus, but a human can't live that way indefinitely at the cost of his own individualism. Sooner or later you'll want to be noticed by potential friends and by the opposite sex. That "hide in the shadows" mentality which kept you alive through high school will start to work against you and the world will seem much smaller, colder and meaningless.
Any success you have in life gets attributed to dumb luck. The mind kills any thoughts of pride in your work. You see no point in meeting new people because "they won't like me anyway" or "I just won't know what to say," which does nothing but fulfill your self-inflicted prophecy. You feel nothing but the lows in life; if you're like me, you may have used drugs to simulate the highs. Thoughts of martyrdom become common after a couple of years because if your life is going to be meaningless then at least your death shouldn't be. This kind of thought process takes years to form and unfortunately just as long to destroy.
And after you succeed, you're still left with lingering thoughts about how many years you've wasted and how you'll never get them back. That particular demon is a serious little fucker because it's rooted in truth. If you've made it this far, though, then you've already faced worse.
I eventually saw the problem and rooted it out, but many people never will. Hopefully this kind of discourse gets through to a few of them.