Sounds like he picked up a bad habit of hiding his choices from his ex, you can help him break that, discuss it with him, get it out into the open in a supportive, positive way, show him that owning his choices doesn't create bad reactions from you. He also may not want to face disappointment from you, and you can show him that it's not what's going to happen. I've been in that boat so many times over the years, on both sides.
Also, besides a stronger mic level, what about some new gear, that makes more vapor? I know that I'm very particular about that, if I hadn't found PVs and tried to quit with Blu's and their weak vapor and taste, I wouldn't have done it.
This. It's not a matter of IF you talk to him about it, it's HOW.
The wrong way would be: I found your cigarettes. Do you really think I'm so stupid that I didn't know? Come on. If you don't give a damn about your health, then that's fine I guess. All this effort I went to to make you juices and help you out and you lie to me?
The right way would be: Look, I know you're still smoking, and really, that's fine. You're a grown man, and you can make your own choices. I fell in love with you as a smoker, and I'll still love you even if you remain one. But if you want to still give switching to vape a try, I could make you some different juices and see if those make you more comfortable with the idea of giving up cigarettes. Just let me know what you'd like to do, and trust me... if you go out for a smoke, I won't think the less of you. Quitting is a REALLY hard thing to do. But I'll do what I can to support you, if you want to quit.
The key isn't to make him feel guilty or busted or like a child. He's hiding his cigs for a REASON and I think Billy hit the nail on the head. I had a friend with a SUPER controlling wife, and the reason we aren't friends anymore is because of her. Because she thought he'd leave her for a younger, thin woman. Because all his OTHER friends were part of an activity THEY did together, and I wasn't (though nobody invited me to the activities). Because all THEIR other friends are MARRIED and I guess I'm a husband stealing harlot because I'm not. Because they don't have separate friends, and because I was closer with him than her, WE MUST BE HIDING SOMETHING.
She's a total nightmare. And he took it. Which hey, his choice. Actually, if he thinks that this is anything even vaguely resembling a healthy, adult relationship, it looks like I misjudged him in the first place.
But he did the same things. Told me lies because he "didn't want to disappoint me". Because Wifey would have FLIPPED if he didn't/wouldn't/couldn't do exactly what she wanted, when she wanted it done. Hid things from me, because Wifey got mad if he drank more than one glass of wine, or looked at anything she deemed inappropriate on the internet.
And I think you SO is in the same mindset. You CAN show him that you're different, by allowing him to be honest, even when he isn't "perfect", and accepting him anyway.