Is it really hard to quit smoking?

Is it really hard to quit smoking? I'm asking this question coz my husband couldn't stop smoking.He said it's very hard to do,he tried it before and got succeded but he return smoking after a year of not using cigarettes.I thought he will never puff again even a single but to my dismay he is much a heavy smoker now.Maybe because he just stayed at home and not much things to do so the cigarettes are now his best buddy :(

I really tried to stop him and I always remind him that it's not good to his health but what I always hear from him is the promise that he will quit soon after our vacation in Philippines.Not only that cigarettes are not good to health but it's also very expensive here in France.I hope he will really take his words.