My DDs were 8 and 4 when we decided to D. XWW took a month or so to find a job and apartment, so we had sort of an in-house S for that time, and that was the worst, for me...knowing, and the kids NOT knowing.
We didn't fight or scream or yell at each other during our M, so it's not like they saw it coming. Telling them was one of the worst parts of all of this, in my opinion. They cried a lot.
Like most BSs here, I was profoundly angry at the injustice: she had the A, she pissed away R, and I was going to see my girls only half of their lives from now on because of it. But while I still despise her for her cowardice and the cost, things have settled down in the past two years since XWW moved out...and in many ways, it's not as bad as I projected.
I do see my girls less, obviously. I have 50% physical custody, and we trade off weeks - this mostly works because XWW lives about a mile away. I actually have my girls some days after school during her weeks with them, because I work from home, and I like having them here.
My girls have done well. It still sucks that this all happened to them, without a doubt, and my youngest (now 6) still struggles with the finality of the D, and with the idea that her mommy and I aren't together in the everyday sense. But she's getting it...it pains me to think that she'll never really remember us being married to each other.
It's sort of cliché (and it always bothered me to hear it said) that "kids are resilient". But they really are. They adapt to the reality and get on. In my case, they know very well that BOTH their parents love them very much, and with me, they know they come first.
And that's been the other, unexpected upside for me: I'm a better father, and I have a better, closer, and more pure relationship with my girls now. I'm no longer hostage to XWW's relative degree of happiness at any given moment, her refusal to deal with her depression, her emotional immaturity, and all her bullshit. And there was a lot, toward the end, including her constant "coaching" and nitpicking of my parenting. No more!
My decision to divorce was ultimately prompted by wanting my girls to see me as a strong man and father - not as a BS. Not as a hostage to another person's happiness. Not as a neurotic, fearful, needy and compromising person hoping my spouse would come around. She wasn't going to, and I'm a MUCH better, MUCH happier parent today for making the call.