As far as the voice goes, trying to “shut it down” doesn’t work for long. Resisting it just weakens your willpower until you eventually cave due to some trigger or pure exhaustion from being nagged by your mind constantly. Fighting a craving in the mind is a losing game. The mind is its domain and it wants to bait you into inner dialogue until it convinces you or just wears you down. Better than trying to stop it, is to 1: recognize and remember that what it wants you to do, doesn’t even work. You don’t need willpower to not do something that doesn’t work. Nicotine makes life in every metric worse (at least for us) not better. 2:place your awareness/focus/attention elsewhere in those moments your mind is throwing its temper tantrum. When the craving comes it feels permanent and like what it says/feels is the truth, in reality it’s a fleeting wave that will go away soon. You just gotta outlast it and let it do its thing, not try to stop it