Drunk words are sober thoughts.

Many times when people overindulge in drink, their protective walls come down and they are not as careful concerning what they say. They will say things that they normally wouldn't say. 
Basically, they quit editing their thoughts and just say what they think.

What you have to determine is whether or not they are speaking from their heart or just plain drunk and babbling. The sages taught that drunk words are sober thoughts, meaning that those who drink too much start to make their true thoughts known, instead of keeping them hidden, when they overindulge. 

Another way to phrase this bit of wisdom is that words spoken when drunk are the person's true feelings.

Either way, the wise man will not overindulge to the point of letting his guard down and saying things which are better off not said. 
Keep your wits about you, especially when you are away from home. Don't overindulge, and if you do, don't do so to the point of not being able to control your thoughts and your tongue.

At the same time, pay attention to what those around you say when they are drunk. You may just find out some "inside information" which they have been keeping locked away from you. 

Always remember, drunk words are sober thoughts.

ps/smoh