For those in 2 year + relationships? please help?

hi, i have been with my partner for 15 years and he smoked, we get on great and its all about knowing each other, if you don't feel 100% about it now then whats it gonna be like in a years time, talk to him and tell him how you feel, you might be suprised by his response, and if he starts being funny with you then is he worth staying with, hope all goes well, and only you know what to do, good luck hun x