why is life complicating?

why is life so complicating? i guess its cos we go thru so many problems before finding true happiness. a lot of ppl say tht just because im 13 i dont have any life expirience. i dont. and i know tht  but why "rub it in"? i guess its cos some ppl just feel inferior so to feel the slightest bit happy they pick on someone less than half thier age! i'm not complaning, they're the ones with complexes and insecurities far gater than most ppl. i mean this isnt my whole point either. so to get to the point i guess its just tht, well, all i wanted to say is, life's short so live it as if everyday was your last. ( i know a whole paragraph just to get tht small point across)...