For all the technical issues (house, kids, dogs, bills, cars, friends, $, ect.) I would definitely go to a lawyer to get the details on how it works in the state that you live in....including the details regarding the kids. Know you don't want it to end up divorce, but separation is usually the first step right before divorce especially when marriage counseling has been stopped. You might as well be prepared with professional information on dealing with it.

Honestly I found that was the most difficult part even because negotiations can get nasty....or if you have someone like I have that is incapable of communicating......it's like banging my head against the wall to get anything sorted out but the marriage wasn't any different.

Also as the others suggested, staying in therapy yourself is always a good idea as it's good to have a place where you can express your emotions & discuss how you are feeling. Having a place to bounce thoughts around at & get impartial feedback......really helps as it keeps a level of logic where mostly emotions want to be.