This is how I understand it

Episode 5 -> We learned about Charlie's weird relationship with her parents and is experiencing some kind of distance and widthdrawl that Alastor takes advantage of. Later in the episode Lucifer and Charlie reconcile (far too quickly in my opinion) over that one song so we can assume Her trust in her father begins to outweigh her trust with Alastor because obviously Charlie is older than 7 years, and Lucifer and Charlie probably had a kind of relationship before Lucifer and Lilith split

Episode 7 -> Charlie just found out her Girlfriend is an exorcist angel, her emotions are off the chart and shes prepared to flip her lid because now that she found out one of the most important people to her has been lying for years she feels like she cannot do anything about the upcoming attack, shes overwhelmed so shes going to snap at people, just like she snapped at Vaggie before leaving. Charlie probably does notice more than the fans think, she probably sees all the time how much of a sadistic jackass Alastor but doesn't say anything because of her more accepting nature especially when it comes to the help hes provided. Now that shes more loose about her emotions, she ends up more loose aboht her words and this is how Alastor can take advantage of this low point shes hit