New Year, New Beginnings?

I know that many of us had a rough year in 2009, myself included. From big things to small things. Despite the fact that it can make one weary and tired I think I have done okay managing through them.
So when the new year came I thought that maybe there was hope for a better year. Seems it was not to be. For some reason out of the blue my fiance of many years decides that it was over, that we are too different now, lashed out at me for his woes, my beliefs/religion, etc. and in general lay all the blame on me. As usual, he makes himself the victim. Something goes wrong he lashes out at whoever is there whether or not it was his fault or not. I'm still trying to figure out why he wants to end it but there's no point. I'm tired of him "breaking it off" anytime he throws a rant so if he's going to try to get back together with me it's a no this time. I'm tired of this, I tried to work things out since he cheated on me for the sake of the kids but I don't think things will get any better if I stay with him.
The last few days or so I've been working out a plan as to what to do...this time I have three kids to think of and they always come first. I have a basic plan so I will try to stick to it and well...just see how things go.