Ok--so in this scenario there's a big question that I think we could use some insight from current/former waiters and bartenders.
GF ordered a bottle of chardonnay. I assume she then took the bottle to the table and drank that for the rest of the mean, right? So your waiter would've sold you the bottle of chardonnay at the table had you just ordered two glasses at the bar. But instead, he missed out on that sale (and the resulting tip) because you got your drinks at the bar.
So the question is this: do the bartenders share their tips with the waiter?
I know in most places, the waiters are expected to tip out the bartenders. I don't know that I've ever heard of it going the other way. So my suspicion is the answer is "no."
If that's the case, then I short-tip the bartender a little bit and I tip the waiter on what he would've gotten had I ordered the bottle from him.
So in practice, let's say the bottle was $100 (just trying to make the math easy). Ordinarily, I would tip the bartender $20. But in this scenario, I might tip the bartender $5 or $10 on the bottle and tip the waiter at my table $10-15, depending entirely on how much time I spent at the bar with that bottle and whether GF ordered another glass at the table after finishing that bottle.