The older son 'T' been smoking for 4/5 years.I have never condoned it .I found he was growing it,asked him to leave,he was arrested, asked him to leave .I have had numerous horrible rows with him about it and he has left the house numerous times but he always comes back. He does not think there is anything wrong with smoking weed every day.His habit has changed him from a bright articulate teenager to a dull,occasionally paranoid young man who works as a labourer as much as he has to to earn a bit of money then has a break and drifts on to doing something else.His close friendship group of around six all smoke and all have mental health issues.However he has crossed the line recently in giving his 15 yo brother weed to smoke as he wanted to try it.My husband agreed he had to leave BUT my problem is I KNOW that T will come back after a break away from the house and my husband will want to let him.Throughout the last four years I have always been bad cop parent and my husband will do ANYTHING to avoid confrontation.I have felt unsupported by him throughout this and T is adept at exploiting this.I really want to separate so that if husband wants to take him back he can and I don't have to deal with seeing him work his way back into the house.Don't know what to do for the best