I'm just over a year into this.
It was me that wanted the split but to the DCs, we said it was both of us that wanted it. That way they couldn't blame one of us.
Don't live together any longer than you have to. Our split was amicable but we had to live together for 6 months and it was awful. We had a couple of big rows, which wasn't like us, and I saw a different side to him.
Ex likes to play the martyr. DCs feel sorry for him as he has shown them he's upset and seems incapable of putting on a normal tone of voice and often sounds a bit sad and pathetic. DCs have absolutely picked up on this and I can see what it's doing to them. Both of you putting on a game face as much as possible is best. Children take on parent's problems and will worry endlessly. A friend of mine is also going through it and the guilt one of her DCs feels because of the guilt tripping shit her dad comes out with is awful.
Luckily ex and I sorted all the finances and we agreed so no arguments there. I stayed in the family home with the DCs so stability for them.
I also don't agree with 50/50. I think this is purely for dad's interests, not children's.
DCs see ex and I talk briefly sometimes when he picks them up or drops them off. He also came over at Christmas but that's not something I'm getting into a habit of doing.
There isn't any ill feelings between us which is good, just an air of awkwardness.
I've been surprised at how quickly they did adapt. It was worse when ex still lived here. DCs got more and more unsettled the longer it went on even though they were told from the beginning when it would happen. Once he left and I told them the new routine (I wrote a copy for each of them and they pinned it up in their rooms) they just accepted it and got used to it.
They still say they would like us to get back together occasionally but they know it won't happen. They also know I'm a lot happier, less grumpy and far less shouty at home. Unfortunately I don't think I can say the same for ex and youngest is starting to struggle when she goes over and a few things she's said makes me think she isn't always happy there. All I can do is try and create a calm and stable environment at home and hope this will see them through. I do think it would have been easier if my eldest had been a bit younger. My youngest has adapted much more easily.