When you stop making excuses for why you can't quit, why you haven't quit, why you're putting off your quit, why you've lost your quit - you'll HAVE YOUR QUIT. For quitting is all about giving up your excuses and being willing to be uncomfortable with the changes necessary to accomplish the freedom you're seeking. It also takes brutal self honesty.
Excuses keep us smoking or return us to smoking. When you understand (through education and personal experience) that smoking is a choice and not simply an emotional, uncontrollable reaction, you will be on your way to a life-long quit. This change, this "understanding" takes a LOT of hard work and education. We don't come by it naturally because the addiction is speaking to our "I WANT" child-like emotional being, let alone our brain receptors.
Get rid of the excuses and you'll not only have a life-long quit right from the get go, but you'll find the beginning journey so much easier. Because when you eliminate the "choice" to smoke in your head, you eliminate the potency of the desire and the attendant cravings.
But you won't know this until you've been there, done that. So go there. Do that. Once you truly "get" excuses - there are none left to bar your way to success.