Friends
Friends do not let friends drive drunk. Let me add to this you also do not take someone's car keys from them and send them to walk home at 2 a.m. If someone is not safe to drive a car they are not safe to be walking home alone. They are vulnerable to strangers. ANyone can more easily grab them and do whatever they want to them. No if you allow someone to drink at your house, especially female you ask them to stay on the couch unless you call a cab or drive them home.
Sure taking the keys away, you are not responsible for that person then getting in a wreck. However you are responsible for the person consuming alcohol in your home. If that person is assaulted, raped or murdered on the way home-- you are to answer. If you do not bother to call to make certain they arrived home; if you can go to sleep given the above, you have no conscience.
I am not proud I drank too much. I am responsible for drinking. However I did learn how one person operates. She clued me in that perhaps she did not care if I made it home. And if I interrupted her "beauty" sleep getting my keys the next morning, I don't care. May she sleep well and be pissed off at me. I am not losing any sleep and I will not apologize.