Somehow I didn’t pay attention to this scene on my initial watch, but I have a feeling it might be very important.
At first it looks like Annalise is talking about shooting night, but it doesn’t really make sense. There was nobody else in the Hapstall mansion that night save for AK, Bonnie and students, and there was a mention that Caleb and Catherine fired all their employees earlier this season.
Cleaning lady’s name, which she coincidentally shares with the woman, who is presumably Wes’ mother, and that shot of Wes when Annalise mentions her son, make me think that Annalise on her Vicodin high may actually be talking about that 10 year old case. She and Eve convinced Rose to testify by promising to take care of Christophe. Something backfired and she committed suicide (or was murdered) because of that testimony. It could explain Eve’s “What did we do?“ and Annalise being “a very good person“ for protecting Wes.