It seems that Letterman has quite a few particularly problematic interviews with female guests.
Instead, Letterman asked more questions about rehab toward the end of the cringey conversation, (viaInsider).
Unfortunately, that kind of behavior seems to have been a pattern for Letterman.

Midway through their conversation, he said, “Forgive me if this is rude.
While Aniston laughed off the situation, she was still visibly uncomfortable, (viaYouTube).
In 2001, Letterman was back at it again.

Because you look like a girl who likes to have fun.”