I drink while nursing... from kellymom:
"In general, if you are sober enough to drive, you are sober enough to breastfeed. Less than 2% of the alcohol consumed by the mother reaches her blood and milk. Alcohol peaks in mom’s blood and milk approximately 1/2-1 hour after drinking (but there is considerable variation from person to person, depending upon how much food was eaten in the same time period, mom’s body weight and percentage of body fat, etc.). Alcohol does not accumulate in breastmilk, but leaves the milk as it leaves the blood; so when your blood alcohol levels are back down, so are your milk alcohol levels."
If I want a drink with dinner, I consume it as I'm nursing. That way, I'm over the "peak" the next time baby nurses.