Marriage Breakdown

My partner and I are going through a very bad patch. We don’t get on with each other anymore and in truth have not done so for the last year. We have tried to hide it from the kids but sometimes we are so angry at each other that we argue and shout in front of them. My 7 and 9 year olds are really upset over this and keep asking me if we are going to break up. I don’t even have the answer myself and don’t know how to answer them?