Softly softly approach to smoking.?

My partner smokes and I really detest it. I have been trying for years to get him to give up by doing the "softly softly" approach. ie. talking, encouraging and supporting him, finding out why he smokes and resolving that etc. however, he just keeps on smoking. He has tried patches, gum, speaking to the Quitline and friends encouragement. Nothing has worked. Friends have tried hypnotism and said it doesn't work either. When I try to talk stronger to him about it he wallows in self pity. The thing is all our friends, including myself have been able to give up in the last few years. My Father recently died of throat cancer so it is really a sensitive issue with me, and although we are due to get engaged soon, I can't commit to a man that smokes. I have come down hard on him now and said that if he doesn't give up there is no future for us. I feel horrible but I am at my wits end. Did I do the right thing?