I've read some of the threads on loved ones with drug and alcohol addictions and have found them to be very helpful. I was hoping someone out there might have some advice for my situation, as I haven't opened up to anyone else about it yet:

Facts: Dated my now fiance for three years in college. We then broke up for 2.5 years and got back together after running into each other at a city event. He lived three hours away so we did long distance for a year, seeing each other every other weekend. He proposed and I decided to move to be near him since I wasn't completely attached to my job and he was (he runs his family business). I took a job with the family business since his Mother needed to retire and things were great. I've lived here for 6 months.

Situation: After living here for two months I learned that my fiance doesn't drink socially like I thought, he drinks every day - at least 5 or 6 beers but sometimes more. Surprise! After confronting him he tried to stop and has not been able to on his own. Then, a month ago, I caught him smoking pot in the bathroom. I had also smelled it in his car. Turns out - he smokes pot almost every day. Surprise! Again, said he would stop and wasn't able to. He voluntarily suggested he seek counseling and has been going for a couple of weeks. I haven't mentioned anything about his use (he hides a lot of it from me) but I know he's still drinking and smoking.

Advice? He knows he has a problem and he knows what it's doing to our relationship, so since he's in counseling do I just wait and see if it gets better? I am a social drinker but have never done drugs, and at this point in my life I'm just not ok with being with someone who has those kinds of problems, especially since I want a family one day. Want to support him and be by his side since he is trying, but don't know when to call it quits or threaten to leave if he doesn't follow through and really stop. Leaving him would mean having to start my life over essentially - new job, moving home with parents for a while, leaving my life. Like many others, I love him so much and just wish he could stop this himself. We have a wedding date set for a year from now, have paid deposits on everything, and I don't know if we should just go on as planned in hopes that this counseling helps? Where's the line, when to call it quits or threaten to leave?

Thanks for any and all opinions!!!