in that case I bet they end up growing up and thanking you. I know I was proud of my mum for leaving my dad and making a better life for us.......he wasn't a gambler, a drinker, abusive etc he was just tight with money, belittled her, ignored us and basically made her miserable and I hadn't realised how much shit she had put up with behind closed doors til I was a lot older. It's been 24yrs, I am close to them both and I know they just weren't right for each other, wasn't meant to be, sometimes that's just how it is.
Oh just want to wish you lots of luck with that and the rest of your journey.
DS was 9 months when we left his father so I didn't have to go through that.
If you can keep it amicable then do, it's confusing for kids otherwise.
Your children will adapt, but do let them know it's ok for them to be sad and that you are sad too. On a practical note, lots of walks might help them too, there can be something quite liberating for chatting when you're outside.
Good luck with moving forwards. It can't be easy but sounds like you are doing the right thing for yourself and your children. They will understand and appreciate that when they are older, even though they love their dad.
Belgianbun - hold on to the fact that your children are not stupid - they will work a lot of it out in their own time. I agree with the 'never slag him off' advice, but at the same time don't lie for him, although with the age your DC's are, try to be kind in what you tell them too. It isn't easy, but it will get better as time goes on.
good luck for the future. I am going through this atm - am moving next week, and when we told ds we:
Told him that basically we didn't want to be married to each other any more (we had been sleeping in separate rooms for some time so this wasn't really a shock to him) I took him to see the house that me and him will be moving to (dh bought me out of this house) We are going to parent 50/50 but I have basically said that access is flexible as much as it can be because I'm not a believer in laying down the law in that regard - things might not have worked between me and dh but he is still a fantastic father and I won't take that away from him or ds. When I got the house keys last weekend I waited until I picked up DS from school for us to go round there and he has been involved where he could and wanted to be.
We are amicable now (I think that me having stayed here for as long as it took for house etc to go through means we have done most of the fighting that needed to be done and so I'm not moving out with major resentment.