In bed, if you're alone, all you're going to do is sleep and a drink or two isn't going to hurt, it will enhance sleep (not good if you've had a skinful but a little is alright).
Driving is a different matter, many are not fit to drive after one glass! Others - big people mainly - are OK after a pint.
Because I am relatively thin and a lightweight regarding booze, I would not drive after drinking even a small amount. Unless a few hours had passed.