Keep in mind that the events in this episode happened in the past, and Pearl has been slowly changing her attitude when it comes to her feelings.

While it is true that during Sworn to the Sword she kept thinking her life was worthless and Rose was the only thing that mattered, Connie and Steven showed her that no life is more important than the other. Thus making her realize how much she had fucked up when Rose was still around and helping her become a better person/gem.

Here she is, the thirstiest rock in universe. In all the galaxies there's no one thirstier than her.
She's reached the top, the pinnacle of thirstiness. Good going, Pearl. You're dreams have come true.

Aside from your dream of getting with Rose of course, because Greg already beat you to it! Haha!