<human>: Can you summarize the given text in a few sentences?

To give some background. We were both moderate smokers a few years ago, I gave up with the help of a book and encouraged her to quit too. She eventually did, but has repeatedly slipped back into it, but has done so behind my back. Quitting smoking leaves you with a keen sense of smell for tobacco: I could smell it on her breath tonight, thinly disguised by some mint, and sure enough, found her stash once she'd gone to bed. This follows months of her never mentioning smoking under the pretence that she had quit. I'm not sure why, but having given after smoking has just bolstered my sincere dislike for it, I don't feel I could stay with someone forever who smokes, knowing the damage it will cause. That might sound hypocritical since I myself smoked, but having freed myself from it had made me more anti-smoking than I was before. I also realise the argument is going to come up that she obviously didn't want to quit in the first place. And though she claimed to at the time, I acknowledge that this is obviously true.
<bot>: We both used to smoke, I quit, she claimed to. Has lied about it since despite me having caught her a couple of times.