I was just wondering if the reason Voldemort was reduced to a half life could be because he split his soul into too many pieces? The night he killed Lily and James, maybe Harry did see the green light from the Avada Kadavra curse killing Lily but then when Voldemort tried to make Harry a Horcrux, his soul couldn't take anymore splitting and that's why he was reduced to a half life?

Just a thought!!!!