How do I help my bf from being such a cynic?

I have been with my bf for 2 years. In the beginning I noticed, he was a little over-opinionated, but thought, hey thats just him. Now, hes outta control! I cant even hear the tv because hes too busy yelling at it about how ugly or dumb is this ?unt! and so many terrible nasty comments about everyone in society. I often wonder what has made him so angry at the world and the people in it?? He did lose both of his parents, his dad when he was 20, and his mum at 30, which i can completely understand the anger at losing ones parents so early and at a crucial age. i know people deal with grief differently but as I have learnt about cynicism, its almost a cowards act to shut himself off from the world, because its too much effort for them to try and learn about others and their ways of life and realise that perhaps you arnt the best and most knowledgable. At one stage a little while ago i was ready to leave him. i just couldnt handle the anger and agression anymore. Because i am not absent from these cynical snide comments either, oh no, i cop it quite often, horrible nasty demeaning remarks. I now have a better understanding of the 'sickness' cynicism, therefore i feel compion and understanding towards my boyfriend, but that doesnt mean I believe what hes doing is acceptable. So I just really need some suggestions or material that will help break this shield of cynicism, something that will open his eyes and heart to a world that isnt so black and miserable as he portrays it to be.