She toyed with people for amusement. She hated Clancy, so talking with her at all about something personal like that was IMO absolutely not straight forward or just small talk.
From the text timeline, the killer was in full-throated rage mode throughout March, really as early as mid-February. Told to get outta there by Travis, fired from Mimi's, flat out broke and likely hiding her car to keep it from being reposssesed, facing forced retreat from Mesa within weeks, seeing Mimi pop up as the "One" after all her fine work to terrify Lisa away from Travis, and from snooping at convention, knowing her besty CL and Travis were trying to hook up.....yah. I wouldn't be the slightest bit surprised if she ran through murder scenarios in her mind as early as that, just to help her get to sleep.