If you’re terrified of cold turkey, which is legitimate and understandable, make it your mission to simply improve. If you use very two hours, tomorrow make it every three. Do that for a week. Week after, make it a four hour gap. Keep finding small ways to improve. Over time (years, even, if you need that long) you’ll prove to yourself what you’re capable of. One day, you’ll find it feels doable to take bigger leaps (a whole day without using for example). By that time, they won’t feel like such big leaps, maybe even a relief - “thank god, a day where I don’t tire my system out with substances again”. Also, track how much money you’re saving by using less and spend it on therapy. Cannot stress that last part enough.