A 34-year-old married man presents for psychiatric evaluation after almost hitting someone with his car while driving under the influence of marijuana. He reports he was prompted to seek treatment by his wife, with whom he has had several conflicts over the past few years about his ongoing marijuana use. He has continued to smoke marijuana daily since the event. He says he has smoked marijuana since he was a teenager, and now it is legal in some states. He does not see what the problem is. What is the appropriate diagnosis?