I need help convincing my fiance to quit smoking.?

We've been together five years and I've noticed that recently he's started smoking more than he used to. At first it was about two packs a week, now its almost a pack a day. I can't stand the smell and the taste when we kiss. I work as a cardiac rehab technician and I see everyday what smoking does to people. I hear everyday from people with cardiac disease and COPD that they wished they had someone tell them when they were younger to quit. There is one particular gentleman who I told my situation to and he said he wished his wife would have tried harder to get him to quit. He said that he was the same way as my fiance, he would get mad when his wife mentioned and it always started a big argument. That's what happens with us. I even bring up that I don't like it and he always says the same thing, "I'll quit when I'm good and ready, but I don't want to quit so I'm not going to!" I know I can't force him to quit but I just don't know what to do. I tell him everyday that I love him and hope we have a long life together but who knows, if he dies of lung cancer at 40 it won't be very long at all. I just need some advice.