I can sympathize, berube... I feel guilty about having ever spent money on analogs in the first place. All my relatives are very judgmental about any kind of bad habits, and I've always been the "gray sheep" in the family (black ones are simply not allowed, LOL). But they also don't understand why I like computers, either. They just run to me for help when they're baffled by modern electronics (such as remote controls for the TV).
I felt horribly guilty when I wasn't working for a long time and all monetary expenditures were severely curtailed, pared down to only food, rent, etc. (But that's addiction for ya.)
However, I have still spent less on vaping than I would have as a closet smoker, even at just half a pack a day. It helped me to know what the math actually is. I'm a much nicer person now because I vape, so it's easier for me to justify this habit. Most people have at least one "vice" (except my relatives, ha) and this is one I thoroughly enjoy, unlike smoking; and it seems comparatively harmless. But I still plan to stop vaping, eventually. In the meantime, it's going to cost something.
Are you alone in your vaping habit, like me? Maybe there are other hidden psychological aspects at work here, besides the actual money involved. HOW we spend money is part of a person's individual value system, and if your personal values are at odds with your actions in life, it creates problems. The judgements of people whose opinions we value can really impact that. Is there someone who disapproves of your vaping? Did anyone disapprove when you smoked analogs? Perhaps the difference lies in the longstanding public recognition that some people do smoke, even though it's looked down on - but vaping seems weird to the uninitiated.
The fact that these devices are reusable, instead of being completely consumed, alters our perception and expectations of them. We don't think of them as disposables. But they don't last forever, so there's a maintenance cost involved - just like having to buy ink for your printer. I know someone who gets mad every time she has to get a new ink cartridge, but she isn't stressed about needing to use paper. Completely illogical... but quite human. Paper costs less per transaction.
Maybe you should sit down with a calculator and figure out approximately what you were spending vs. what vaping costs, and even set a budget for yourself. It can help you feel more in control of your choices, especially if you can measure the difference and see whether you're actually coming out ahead or not. Not knowing that could be the real cause of your stress. If you find that over time, you're spending less (while also getting a better value for your money in terms of health and pleasure), the guilt might just disappear.