hi ftj, by laziness I meant that maybe it was easier to accept him than psyching yourself up to reject him - it was just one possible reason I suggested and there may have been other possible ones I didn't even think of. My advice is just that you should try hard to know your own mind, because that will make it easier to decide what you want to do and how best to go about it.
It's good if you're able to be financially independent, it means you don't have to stay with someone who's stopped loving you simply because you can't afford to leave. I don't suppose it will mean it's any easier emotionally to decide, though.
I don't think it will ever be possible to regain the past. Even if you stayed together you would still have the knowledge of what he did, however hard you tried to forgive and forget. If you think there's a way to save your marriage, go for it; it's always the best solution, especially when there are children involved. But as I think I said before, it sounds as if he's lost interest in trying, and it's not something that can be done by just one party. But if you're going to leave, you need an exit strategy - knowing where you're going to go and what you're going to do. I don't know if he's going to be willing to continue supporting the children, so you may have to consider whether you want to pursue him legally - it's not easy, legal action takes a lot of psychic energy you might prefer to save for raising the children.
There's no easy, low-impact solution to all of this, but it's important to deal with your own feelings so you're at ease with what you decide.
I am off to bed, it's 2.30am on this side of the Atlantic. Good luck.