Just some unsolicited advice... first, you are younger than me but we both smoked 41 years. I assume you are at the point where you don't need me to tell you that you need to quit the smokes, for good, and sooner than later.
You apparently successfully fully quit, at least for a few days, right off the bat. I can tell you, with two parts experience and 4 parts what I read here from others (that had the same experience I did) that if you do relapse, it will very likely be very much more difficult the second time around. If you can quit once and done, there may be a lot less pain than if you do two or more rounds.
So... a lot of this is will power and the motivation to really quit, and for more than a week or a month. The other part, though, is making
sure you never, ever don't have at least one working
vape. The money does not matter and your GF should be more than willing to forgo a pair of shoes or two to make sure you stay quit.
/end of unsolicited advice