Confidence doesn't come easy when a intimidating, critical grandmother brings you up in a house full of worried old people.  Seeing your parents in the hospital, debilitated beyond recognizing you, is terribly sad.  I imagine his greatest desire would be quite similar to Harry's: get revenge for your family.  That's what's missing in both their lives because of Voldemort and his right-hand woman.  He isn't that smart about most things people care about, but he's down to earth, real, honest, and full of integrity.  Neville overcomes his shame of his parent's condition to see them as the heroes they were, and he worked hard to become like them in spirit, yet be his own person with his own abilities.  He also learned not to value one person over another based on their strengths and abilities but by their character, their heart.  He was a good side character, but his part is over in the Harry Potter series, I think.

i think neville is actually a lot more complex than people think cos he lost his parents and everone thinks hes a dumb ass but hes actually quite cool. end of.