Yeah, I do think the other ladies make some good points. Let me share my experience with you...When we got married my husband chewed tobacco and I hated it, a lot! We had lots of discussions about his health, etc. etc. We didn't have kids at the time but I even pointed out that he'd want to be a good role model and he might as well quit now, etc. He really did agree with me, but it's hard to stop. I knew that, but it was still hard for me to accept that he wouldn't just "make it happen" for me, our relationship, etc. I knew I was being a little crazy, but I just couldn't help it. I loved him, I was concerned, it grossed me out, you get the idea! ;)
He lied to me a few times about it as well and I went a little nutty. But, in the end I finally sat down with him and told him, hey I don't want you chewing and I'm not going to like it, but I like the lying way less. So, if I ask you, be honest and I will try not to be crazy. It worked much better this way. We also agreed that he could not have it in the house under any circumstance and he followed that rule. I did not go looking for it in his car or anything b/c frankly I didn't want to know, because I knew I'd get mad! In the end, he did end up quitting because he really did want to, but he just couldn't deal with my volatility on the situation.
I think explaining to your husband your real fears and concerns and listening to his and then coming up with some sort of a compromise that you both feel is fair is step #1! Hang in there, marriage is hard and this is one of those things that you just have to figure out!