As several people have stated the first step is to get yourself a lawyer. Don't turn yourself in without an atty. you'll sit in jail longer while you are processed. There is no avoiding being processd and spending several hours in your county jail. A lawyer can speed things up.
My girlfreind works for a doctor and a patient some how stole an rx pad and eventually got caught writing rx's for himself. This guy was forging illegal prescriptions and he got probation. Apparently this guy also had prior convictions for the same offense. Point being I don't think your in serious trouble, all though the biggest fear we have is fear of the un-known. Step 2 get youself some treatment. Not only so it looks better in the courts eyes but for the sake of yourself and your kids. Try not to stress and don't run into the police without a plan! Good luck.