My boyfriend's drinking and partying habits make me uncomfortable. What should I do about it?

I believe the most important thing is communication. If he does not yet know that it makes you uncomfortable than he is unlikely to stop as he has no incentive to really. However if possible you could have a clear conversation with him about how these habits are making you uncomfortable or bothering and maybe compromise with him. It is important that the conversation does not sound demanding as this may unintentionally upset him, being straight forward with how you feel is key here. If after his habits still do not change than it is important to show how vital it is to him that you feel commutable in a relationship.