How to explain/ justify separation to the children?

[AvaloniaFunk]

Myself and my partner have agreed to separate.
No one else involved, just many years of feelings slipping away. Much of this can be traced back to my partner not being the step dad to my son that he needed and deserved. In fact damage has been done due to partner's immaturity and anger issues. I should have drawn a line years ago but didn't. My eldest is grown up now and at uni and we have two children together aged 8 and 10.
We are preparing to sell the house and go our separate ways once it sells so need to tell the younger children really soon.
What do I say? How have you explained / justified separation to children when it is not appropriate to explain the full truth? I want to do this in the most emotionally- healthy way possible.
Any advice welcome.

Try to think of a friend that your little one knew a while ago but they don't get on with or moved away, so they can relate but feel that's ok and normal. The most important thing is to make your child(ren) feel it's not their fault, that Mum and Dad love them, whatever happens.

Put yourself in their situation.

It takes a lot of strength though, especially when your ex is nasty to you.

I said Mummy and Daddy aren't making each other happy and we feel it would be better to have two happy homes than one unhappy home, but we both love you very much.