I never smoked, but people who smoke told me that quitting smoking is not as easy as it sounds. As far as I understand, it's like when you really want to eat a cake, when you are on a diet, but 10 times harder.
Yes is it kinda like that, You can also replace smoking with eating because it releases dopamine in the brain, that is why a lot of people who stop smoking will gain weight.
I think finding a replacement is a good thing to do but it should be healthy otherwise you will just trade 1 bad habbit for another bad one.