Not that I disagree with you, but can you explain why you think this means drugs? Is that particular expression one that it known to be related to drug use? Maybe so. Maybe she was just wanting to drink more? Maybe she went to JR's room, scored some whatever and OD'd. Who the heck knows.
Partying is a euphemism my friends and I will often use to distinguish between just drinking and more extreme substances, Mrsu. That's why it immediately jumped out at me when the roommate of the friend Lauren walked home used that term. And thanks Bloomington for the info about coke on campus and Mrsu about the reports of there being other drug issues on campus. All college campuses have drug issues to some extent. I went to Yale and, even though Yale isn't considered a party school by any means, some students on all college campuses do drugs. It's just a fact of life in the 21st century.
And I'm not sure if it was Bloomington or someone else who said that Lauren showed a lot of activity for someone who was drunk that night. Alcohol does tend to be a depressant while coke and a lot of other drugs are stimulants. (And I'm not saying Lauren must have been on drugs -- just speculating to try and figure out what happened to Lauren.)
And VeryVeritas (which reminds me of Harvard, speaking of colleges

) that's what I'm getting at in talking about Lauren's motivations that night. In reading more of the details about that night, she showed a lot of activity that's potentially increasingly motivated in one direction: she started out with her friends at home, I think, but then went to the bar, back to her apartment, maybe just to get another pair of shoes which she abandoned after the fight, walked her friend home and then went to a second friend's apartment afterward, after mentioning partying.
I think it would be pretty natural to call it a night after walking the friend home at that hour given that she had no shoes, it had been an eventful night and it's not like the second friend was having a general kegger party. But the thought of partying brought her to the second friend's apartment which makes the whole night seem less like she was looking to cheat or hook up and potentially looking for something else. And, if I was going to pick a POI out of the friends/boyfriend, that second friend who was the last to see her stands out because the trail ends with him and partying made her think of him.
I do think the whole romantic triangle thing is compelling but, after hearing some more details, I'm just not sure that's where Lauren's head was. And her boyfriend, knowing her well, may have known that her motivation may have been less likely to be cheating on him but possibly experimenting in other ways. He may have been protective in that sense and that's why she wasn't partying with him that night.
Just throwing things out there that are possible but may become less likely as more information emerges
I just hope the police are investigating every avenue and also that Lauren's friends don't hide information that could help find her because of the drug taboo. There are things far, far, far worse than drugs and it appears that something far worse may have happened to Lauren. :cry: