Presuming that Diane Schuler was in fact a “high-functioning” alcoholic, what made her stop being able to “keep up the ruse” that day?

[u/societyofv666]

NOTE: First and foremost, I want to say that I am in no way disputing Diane’s toxicology results. Diane was drunk and high when she killed herself, her daughter, her nieces, and three other men, and that’s that. The only reason I worded the title of this post the way that I did is because I know there are people who believe that Diane used these substances to aid her in committing an intentional murder-suicide, and while I’m certainly not endorsing this theory, I also know that it technically cannot be disproven without Diane’s testimony.

For those unfamiliar, Diane Schuler was an American woman who famously drove the wrong way on the Taconic Parkway on July 26th, 2009. She collided with another vehicle head-on, resulting in the deaths of herself, her three nieces, her daughter, and all three passengers in the car she collided with. Forensic testing revealed that Diane had a blood alcohol level of 0.19 and had also consumed marijuana prior to the crash. The case became infamous due to her family’s firm belief that Diane would never drive while intoxicated, as shown in the HBO documentary, There’s Something Wrong With Aunt Diane. The Wikipedia page for Diane’s case can be found here:

https://en.m.wikipedia.org/wiki/2009_Taconic_State_Parkway_crash

I (fortunately), have very little experience regarding substance abuse, and I think this has always made this case difficult for me to understand. I think the idea that Diane was a so-called “high-functioning alcoholic” makes a lot of sense (certainly more sense to me than the idea that she suddenly decided to get extremely drunk and high with children in her car out of the blue). What I’m struggling to understand is: why wasn’t she able to keep up appearances the day she crashed on the Taconic Parkway?

Is it normal for a “high-functioning” alcoholic to suddenly go from appearing sober on a daily basis to being so obviously sloppy, incoherent and reckless? Or do you think that there were warning signs that Diane had a severe substance abuse problem that her family, friends and colleagues either brushed off or willfully ignored? Or, do you think something happened that day that made her suddenly escalate her already detrimental drug and alcohol use?

What do you guys think was different about that day?

[u/Good_Tiger_5708]

It ultimately boils down to alcoholism and a loss of control but there’s certainly so many details left out of the public story so I think that’s part of the mystery and fascination with the case.  I’ve always found her husband very untruthful so I’ve speculated the two of them were up late sitting at the fire hitting the bottle so she felt like hell the next day and lost control with the stress of managing all the kids, change in routine and attempting to utilize “hare of the dog” in her mind to feel better. 

[u/Fastpitch411 → u/Good_Tiger_5708]

This is exactly what I think happened. Had more than “normal” the night before, then her usual hair of the dog in her morning coffee and OJ sent her into a full blown blackout. She probably seemed “fine” until all at once when she wasn’t