Whilst I agree there's far too much negativity on the news, I think it's a little melodramatic to say it's killing you.
Maybe I'm just good at switching off (emotionally, that is), but I very rarely struggle to sleep at night. Whether I watch the news or not. I must admit, I try not to watch TV these days and spend half my life on my laptop instead. But I use facebook and my feed contains plenty of news feeds so that I can keep up-to-date with what the maniacs in the world are up to.
There might come a time (general elections, say) when I'll be trying to vote the British ones out.