Totally with you, OP.
It takes a multi-pronged approach. Hypnosis is good.
Positive affirmations/helpful thinking are good: rather than feel like you’re depriving yourself when you try not to eat some chocolate, tell yourself something like, “I’m looking after myself”, and be happy for yourself.
Allow yourself some chocolate from time to time. Eat a small piece mindfully. Really slowly. Smell it first, breathing it deeply. Then nibble a bit, let it melt on your tongue. Next nibble direct to a different area of your mouth. Chew it slowly and deliberately. Breathe in while there is chocolate in your mouth and notice the smell and flavour. Take your time. Take lots of time. Focus only on the chocolate. Experience that small piece of chocolate as completely as you can. It sounds mad, but doing this can make one piece of chocolate incredibly satisfying.
Keep the rest of the bar in the freezer. Frozen chocolate is nowhere near as nice as room temperature, so keeping your chocolate frozen will help you pace your consumption.
Part of this mindful chocolate is that you choose when you eat it. You eat chocolate when you are not hungry, when you are not exhausted. You eat it when you are in a positive frame of mood. That way you reframe the association that so many of us have that chocolate lifts a bad mood. (God knows it doesn’t work!).
If you’re hungry, have a hot drink. If you’re still hungry, have a little snack. If you’re still hungry, it wasn’t good or drink you were hungry for. What is that hunger: boredom, loneliness, frustration? Chocolate is not going to solve any of them.
If you cut down your consumption of sugars and sweet foods you will find chocolate calls you less and a small amount satisfies you more.
If you’re looking for that sweet, smooth mouthfeel, try drinking Licorice tea. I like Teapigs and Pukka, good strong flavours. One bag, particularly Teapigs, makes much more than one mug, so they cost about half as much as they appear to cost. I prefer to cold brew the tea.