^^^ agree ..... Not only that but you must ask yourself the question as to if your girlfriend is worth sacrificing your life for? After all none of us knows the long term effects of vaping. If your girlfriend and you were standing at the edge of a cliff and your girlfriend said she was going to jump to her death, would you jump to or would your natural preservation instinct take over and stop you from doing so? I would think that if a person truly cared about someone else then they would want to be healthy, strong, and stable for the other person and not the other way around.
I am usually a person who cares less who starts vaping and never say's anything to any individual who starts. But in this case, I think your reasoning for doing so may be a bit immature. Not meaning any offense towards you, but I do want you to seriously think about your decision.
A minor problem with this analogy...
Jumping off a cliff has a 100.000% chance of killing him instantly (assuming enough height)
There are no known and proven health risks of vaping. None. Zero. All the hand wringing over vaping is an argument that... we don't know enough, despite the fact people have been vaping for over 6 years now, and how long is long enough? Or... prove a negative, which is impossible to prove, philosophically. Prove vaping is 100.0000% safe. Of course, that standard, applied to anything we do in modern life, even talking over a cell phone, would result in strong recommendations to cease and desist.
Other than that, the analogy is just fine I guess.