There is nothing to it, you just decide "fuck this shit, I'm done". That's what I did, that's what happened for people I knew that stopped any addiction you can name whether that's smoking or drinking or otherwise.
People build up big fables around their vices and paint themselves as victims or underdogs or sisyphus type figures or what have you. Heres's a secret: it's all bullshit.
It's neptunian - you have the addiction, but also the delusions, the dissolution of self, relinquishment of control, the victimhood, the unconscious. Self undoing comes from within and from without. A negative relation to yourself spurs you onto doing things that are harmful to you, which feeds further into a negative self perception, and so on.
You are not powerless. You are in control and you have the ability to execute your will regarding yourself in whatever way you see fit.
Direct your attention within yourself and figure out why you do it.
It can be you trying to fit in or have something in common with people.
It can be a coping mechanism for emotions. For example, a passive form of self harm stemming from self hate.
It can be a surrogate activity for artificial fulfillment of unmet needs.
It can be hedonistic pursuit of sensations.
It can be identity related, feeling egotistical gratification in some way, or trying to fit an archetype(smoking for example can be seen as blue collar, low class, or seen as edgy or "cool"). This can also apply in a twisted sense, for example you you can believe that you deserve harm or death or generally bad things. The vice is an affirmation of that identity. The vice is therefore a symptom of a deeper issue.
It can simply be carelessness for the consequences. The toxicity of smoking(and vaping, they are interchangeable) are usually not felt immediately, so you don't take it seriously. You take it very lightly. The damage is not realized in your mind.
Once you figure out why you do it and develop that self understanding, then it becomes much easier to stop. Many people allow themselves to fall victim to the consequences of their own unconscious decisions.
There are people who won't quit smoking even after hospitalization, after being unable to dress themselves without being winded, after coughing up blood, and hearing wheezing, creaking and gurgling from their own lungs. They'll blame everyone and everything for their self destructive actions, even the substance itself. They'll do anything but take ownership and responsibility and acknowledge their part in it.
It's critical to understand why you do it, to banish ignorance, understand what it's costing you, and to exert your will and awareness over your own life.
The vape doesn't put a gun to your family's head and tell you "suck me". This habit stems from you and therefore it ends with you.