Having quit this year (after a long time of cutting down/vaping etc) I think my main advice to you will be this:

If you relapse it isn’t the end of the world, it’s just a bump in the road. Don’t be too hard on yourself, it’s not easy.

Also, keep a pack of smokes or a vape or snus or whatever you use on you for a week or so after you stop using them, so when you feel your pockets you don’t panic when you’re missing something, which will set off the response to “I need nicotine”

Good luck!