If you're struggling with wanting a glass or two now, while you're sober, think how much you'll be struggling with wanting another glass or two if you have that first glass or two. And once you've had that next glass or two, well, that's nearly the bottle finished so no point leaving the rest of it. And there's bound to be another bottle somewhere you could crack open, since everyone seems to be enjoying themselves. And another one to crack open once everyone has left, just to unwind of course. And another because... Well, you can't remember why you're drinking at that point, but probably don't really care any more.
You can see where I'm going with this.
It's far, far easier to say no to that first one. And you get to wake up feeling great, proud of yourself, and knowing you didn't say or do anything you regret.
Hang in there, you can definitely do this.