Yeahhhh, I hear excuses and justifications here. Stop - full stop.
I also worked as a server and bartender and while I was drinking during almost all of this time- I didn't have to. Also know other (one specific one I am thinking of- a VERY successful longtime bartender) who don't drink.
Turn the focus on others' fun - a "that way you have all the fun" kinda thing. But you need to stop letting this all be an excuse, or even just a situation where you are setting yourself up for a "slip."
I don't think you've lost your 15 days but I think continuing this way is setting yourself up to blow your sobriety, full stop.
This may sound harsh, but sometimes the truth is. What do you want most? To be sober or not?
Good luck.