Dd i think you should not be so hard on yourself mate. See it like this: I have quit smoking 7 years and 9 months ago a few years back when I wad drunk at new years eve I took a puff of a sigaret to show myself I hate it and even drunk I indeed did. I don't see one puff as failing. I was curious. I know ur saying you have cravings now so i understabd it's different but hey it was only one sip mate you didn't have the whole drink so I think you should get cudos for not drinking the drink!
Hugs and don't beat urself up mate! Life's too short for that focus on the goid things! You only had obe sip didn't drink the rest and dint get drunk