I think the only reason I commit to the gym is because I get to smoke a cigarette on my way
That feels counterintuitive. Why do you go to the gym again?
Yes, I also think I'm getting a little bit fitter and that feels nice to me
Then you should keep working out as exercising daily is very healthy. You need to kick the smoking habit though, it will counteract with all the work you do at the gym. Smoking can cause cancer and you are dooming yourself to an early death.
So you think I should quit smoking?
Yes, you should quit. Not only it's dangerous to you, but it's also dangerous to people around you with your second-hand smoke that can also give cancer to people even if they're not smoking.