What others think about me is not something in my direct control, nor do I want that responsibility, and, frankly, it's none of my business. I find it exhausting trying to get everyone to agree with my POV, so I gave up on it a long time ago. Others are lagging behind, apparently have more energy than I now have, and can continue "the good fight."
Here's how I handle the dilemma you describe, though. I agree with them. Yes, I'm addicted. But, based on the research that is known, vaping is not harmful, and/or certainly less harmful than smoking. I may even elaborate, if I care enough about their "concern." No one has ever died of a nicotine overdose when used as we do, to my knowledge, and I've searched for this answer. Lung cancer represents 30% of all cancer deaths. Nicotine is in our food chain, so if you like your vegetables, you're ingesting nicotine. Nicotine is now commonly used in the treatment of a dozen diseases and therapies, with no known side effects. I am certainly doing less harm than smoking, and their "support" is appreciated.
In truth, if I'm doing something that is good for me, like substituting vaping for smoking, and anybody wants to give me too hard a time about it, particularly judging me morally, I tend to spend a lot less time with them; friends, family or otherwise. I need to take care of myself, because apparently, no one else is going to do that for me. If, after I explain the truth, as I understand it, and as can be found on this forum, and "these people" still want to judge me, then the problem may not be me, or what I'm doing, it may be just them. Most smokers are not "conformers." We tend to be rebels, to one extent or another. I suppose there are the victims as well, but most of us didn't care about what people thought when we were smoking, at least not enough to quit. And if we couldn't quit, for whatever reason, and we have now found a way to quit, by vaping, and others are not supportive of us, we still must be true to ourselves, try and explain the truth as we know it to others, and the rest is OUT OF OUR HANDS....period.
I understand your need for a counter argument. How about your health, your life, one step at a time, a little credit where credit is due, or even mind your own business, when necessary. The fact is that you might not be able to satisfy other people's requirements of you, no matter how well intentioned, and why should you even have to? Or want to? Sometimes we just have to agree to disagree, and there is no "winner." I don't waste a lot of time trying to get people to agree with my POV. I have one, they have theirs. Sometimes there is common ground, sometimes there is not. I don't live my life based on their POV, I have my own mistakes to make, just as they do. If I focus on them, then I'm making the same mistake they are making. These are my own "big boy" decisions, whether anyone else agrees with me or not. I find in vaping that I am far more respectful toward others, than they have ever been toward me, and I prefer it that way. My two cents before I have had my first cup of coffee.