You need to consult a lawyer about this, because every state/province has different laws. I've heard of mothers applying for the exclusive temporary use of the family home, in case of abuse or addiction, which effectively prevented their spouse from coming him. They then initiated divorce proceedings and custody proceedings at once.
The issue may be that your AH's name is on the mortgage, in which case, he has the right to be in the house, should he cease to be so benevolent and decide to return. I can't remember if you have children or not...