Welcome to SR..I was a Domestic Violence Advocate and Educator for my local womens shelter an I find his thoughts of killing you to be extremely serious. There are several things to factor in also, does he have a history of violence, own or have a fascination with weapons, history of abusing pets or people,have a history of stalking, history or signs of mental illness, made threats of harm to you, himself, or anyone else? If it were me I would talk to someone at my local womens shelter, they can help you with a threat assesment or something similar..what does counselor say? 11 days off booze is not very long and the way you are making it sound he doesn't seem very committed to recovery. The most important thing here is not his sobriety, but your safety.