I can only offer you advice based on what I went through, which is pretty much the same thing you are going through right now. You need to do the following 2 things:
1. Do not move out of your house until a lawyer has advised you that it is safe to do so. Moving out before you get clearance can have major implications. That being said, if you can find a place to stay, or rent a room, you and your wife can hammer out a temporary parenting schedule, or what is commonly known as a 'nesting arrangement.' ie. you each take turns living in your home and taking care of the kids while the kids stay put. This ensures that nobody is giving up their claim on the house, while the kids stay in one location while you and the mrs try and work out whatever details you need to work out. Trying to work out seperation/divorce issues while the 2 of you reside at the same time in the same residence is a recipie for a domestic criminal charge--this is a very real potential that you need to take seriously. Your wife simply has to pick up the phone and you will be charged criminally. Once she does that, you are out of your house, you may have given up your financial claim to part of your house in the eyes of the law, and you will definitely never see your kids again unsupervised until a court clears you. Do not take this lightly. Do everything you can to avoid a situation where you could get charged by your Mrs. A good nesting arrangement will go a long way to saving you money and stress. You can nest as long as you need to while you save up money to retain a lawyer. If you can work out some kind of nesting schedule with your wife, it will allow you a chance to either divorce amicably, or save the marriage if that is still of interest to you.
2. Get some kind of counselling, or, go to a gym, or learn to meditate, yoga, spiritual retreat, whatever. You are about to enter into one of the most challenging situations life has to throw at you. This is not like breaking up with a girlfriend.. If you deal with this by getting angry, doing drugs, binge drinking, binge whoring, whatever, it will all be used against you by your ex in court. Learn to deal with this in a sober way. Keep your mind and your body strong for the battle ahead.
Best of luck brother, you will be ok if you follow these two pieces of advice.