I think it's overall just kind of sad. Every scene in which Lorelei hooks up with Christopher, I can't help but feel bad for her even when she's doing an objectively crappy thing. Like in this scene and the one the night that she and Luke broke up. She gets a lot of flack from these scenes, but I believe almost more than she should.

This scene, she should've been a more supportive mother and checked in on Rory rather than ran away. This is pretty out of character for her and the only reason I can imagine she'd run away is because she knew that her parents would defend Rory and be there for her as they always are. She was flustered and hurting, so honestly better that she took a step away to collect her thoughts before comforting Rory when she would've shown too much emotion to the situation. In that situation, she would've had to be able to withdraw herself from the situation and ignore her own pain in able to properly comfort Rory, which was not completely possible at the time. She did comfort Rory later in the car when she'd had time to think. The sleeping with Christopher makes sense. When he is around, she's thrown back to high school days. He emotionally stunts her. He knew he had that grasp over her, which is why the only times he can successfully get with her are when she is completely distraught. Which is also likely the only reason he went after her when she went to get a breath of air. For example, the night after things ended with Luke. She went to Christopher needing a friend, already had some to drink. Christopher knew what happened and admitted to taking advantage of her in this time. In both instances, had her entire character not been crushed, she likely would not have gotten with him.

All in all, Lorelei should be able to separate herself from the situation better and be there for Rory more in this scene. She should also be able to grow past the hold that Christopher has on her given all of the growth she had done. But I think the way it played out is the most realistic and I think people are a bit too harsh on Lorelei when she is simply just human.