I've encountered a bug with Palla. I've been confronted by Shawn and she just hasn't returned.
Does the condition maybe check for /exactly/ 7 days since the confrontation? Because if so it's possible to lock yourself out of Palla, without warning, by not being home at a certain time.
Viewing post in Love & Sex : Second Base comments
For the most part, I find that most events like this happen on a Saturday afternoon. I try to not even make any dates for Saturdays because I have had events happen and piss off my date because the event has made me miss it. From noon on, I stand in the living room and hit the pass time button. Hope that helps.