Nicotine per se is not substantially addictive; as found in cigarettes, the MAO-inhibitors (anti-depressants) - nicotine combo is the reason behind smokes being 'that' addictive. Then again, there are many other aspects behind tobacco cigarettes being addictive. This will even vary from person to person.
While you have "technically" become a NON-SMOKER, it could be said that you haven't entirely quit the behavioral aspect and nicotine. This is not DEADLY and functional. You could gradually reduce your nic intake as in a NRT fashion, and eventually vape 0 nic. While this is probably "politically correct", nicotine is not really any worse than caffeine, so it is a personal choice.
Moving to nicotine pharma products is NOT a sensible option. And while your boyfriend speaks out of ignorance, he may be worried for your health and you should bear in mind that there is an instinctive tendency to react this (stupid) way. You should inform him that your nicotine intake is as bad as his coffee... You could even do some research on this together...
Then again, vaping is obviously MUCH SAFER than traditional smoking and totally safe for the ones sorrounding you, but the long term effects are not determined yet. This may be a good reason to quit vaping eventually if you want to stay on the totally safe road. Flavorings (mostly) may not be totally safe. However, it is logical to assume that this safer alternative to smoking is pretty much safe.
Many, if not most, of us did not want to quit in the first place and have become 'vapers for good', so to speak. Spend some time reading and studying this together with your boyfriend; make doctors or professionals (who are 'updated' that is...) let him know about this facts... You boyfriend will eventually understand.
Welcome.
You will find a lot of useful information in this very forum... Threads; links; research; etc. Browse through it!
"Ad astra per nidor"
PS: Is your avatar's pic "the real you"? Just curious...!