Would you stay in a relationship with someone who is dependant on weed?

I guess I am just after the perspective from other people as to what they would do in the same situation. I currently live with my partner and have 2 small children under the age of two with him. The only problem is all he ever thinks about is weed and if he goes one day without it he turns really grumpy and snaps instantly at the children. He wont hardly speak to me either. When he has his weed he is fine . I've already told him about 6 months ago that things have got to change. He did try but is now back to it full swing again. I wouldn't have a problem if he didnt smoke it so heavily and didnt get so grumpy when he dont have any. So what would you do? Would you stay around or leave? It makes it more complicated when there are children involved.