It’s the fifth of forty days of Lent. By the end of your writing today, your character will know in their heart he or she will either make it all the way through Lent with the behavior they are changing intact… or failure is inevitable. He or she will know, period.
He wipes the sweat from his face and knows he can work out for an hour every day; he knows he won’t miss because it feels too good to hit.
She can feel the F-bomb on the tip of her tongue, pressing so hard against her teeth and she’s ready to turn it into “Fffforget it!” and she’s not going to “go there” with him, anymore.
He stares at her thumb on the wheel of the lighter and knows that familiar flick, that *shink*, that spark, that drag, that rush, her closed eyes, are mere seconds away.
You may not like his or her answer. But remember: this character has his or her own life and he or she knows who they are; your job is just to learn about them.
Give this exercise fifteen minutes of your time. Be sure the ending makes it clear where his or her heart stands.
Write it up and see what happens.