Why do democrats and republicans hate each other so much for?

Ok so im not really on any side here, I agree with things on both sides with different issues. I was watching a lot of videos on congress and different issues the plague our country. Wouldn't it just make sense if we could all just get along? Or just not have the democrats and republicans? All this does is split our country into two parts. We have children dying and starving on our own streets, we have our men and woman serving over seas. Our economy is in shambles, and we are worrying about bombing libya. If the argument is for the oil they produce well they only produce 2% of the worlds oil. Im just confused is why do we always have to go and try and fix other countries when ours is hurting? And please dont give me crap about how awful obama or how great obama is thats not what I want to know.