Why don't Garnet, Amethyst, and Pearl care about other gems?

When I was rewatching Monster Buddies looking for evidence for my Centipeetle theory, I noticed something strange. The Crystal Gems, especially Pearl, were surprisingly hostile to Centipeetle. They attacked her whenever she felt threatened, even though they knew Steven could easily calm her down. Pearl even makes a point to call her a "thing" with disgust written all over her face and tone of voice. This all made sense back when we thought gem monsters were just, well, monsters, but now? Not so much. The CG's treatment of a tame corrupted gem who could clearly understand at least Steven ties in with something Lapis said three episodes later. "Your friends, they don't really care about other gems. All they care about is the earth." She's definitely right about that. But why don't they care about other gems? Pearl: I thought Pearl's words in Monster Buddies and Mirror Gem were especially shocking because she knows what it's like to be treated as a "thing." If she can be so amazing despite being "just a pearl," then she knew that Homeworld's treatment of gems like her is bad, right? Wrong. She actually agreed with that view. Take a look at that one line in Friend Ship: "No matter how hard I try to be strong like you, I'm just a pearl. I'm useless on my own. " I relate to this so much it hurts. That feeling that no matter how much effort you put into something, no matter how much you excel, there's still one part of you that makes all that hard work worth nothing. It can't be changed, or fought, or gotten rid of. You just have to accept that a core part of who you are is always going to be there to remind you that everything you do is in vain. Obviously, this notion that one flaw (even if it isn't really a flaw) can invalidate all of your achivements is unhealthy and outdated. That's where the second point comes in. Rose was the first gem to validate her, to "[make her] feel like [she] was everything." She probably thought that Rose was the only one who could make her feel like that. She thought that she needed the love of someone she looks up to to be more than just a "thing." The problem with this can be summed up with an old proverb: "Give a man a fish, feed him for a day. Teach a man to fish, feed him for a lifetime." It's all well and good to just feed someone fish, until you're unable to supply it to them anymore. Pearl stole fish from Garnet, who got mad, but decided to teach her how to fish for herself upon realizing how hungry she is. Now that she knows that people don't need validation from others to be valuable, Pearl will probably be more open to the redeeming of other gems in future episodes. Garnet: While Pearl straight up looked down on other gems, I think Garnet is mostly just trying to do what's right. Let's look at a few examples of her attitude towards fellow gems. Jail Break- Steven: How many more gems are trapped here? Ruby: Don't know, don't care. From this I can say that Garnet, at least somewhat, is too consumed with self-love to care about other gems. Ruby and Sapphire want to be together more than anything, and they had to drown out the hateful opinions of Homeworld Gems to do so. Maybe this resulted in her ignoring all Homeworld Gems and seeing their opinions as invalid. Monster Buddies- Garnet let Steven try and tame Centipeetle without much fuss. She was even the one to suggest bringing her along on the mission. She only attacked when she thought she would hurt Steven. Other gem monster battles- Most other corrupted gems aren't nearly as tame as Centipeetle. And since she has Future Vision, Garnet has probably witnessed the deaths of her friends at the hands of these monsters more times than I'd like to imagine. Catch and Release- Many people have expressed distaste at Garnet's haste to poof Peridot. If you look very closely, though, you can see that Peridot was aiming right at Pearl's gem before Garnet grabbed her. Garnet had every reason to assume that Peridot's pleas were only a trick to distract the CG long enough for her to kill one of them. However, she was still wrong. Peridot was telling the truth about posessing vital information. How many other times has Garnet poofed and bubbled a completely innocent gem who she thought was just telling "the desperate lies of a gem who's been caught"? Maybe Lapis' situation was similar. Amethyst: Amethyst's reactions to the sentient mirror confused me at first, because they seemed to contradict each other. She looked incredibly guilty at first. Almost immediately after, she said "Yeah, let's bubble it!" with an evil look on her face. The episode "Reformed" gives us insight into Amethyst's character that can help us solve this problem. She doesn't want to think about herself. She tries to hide all the things she hates about herself. She also looks to Garnet for approval, which is revisited in "Cry For Help" when she expresses excitement at the idea of Garnet thinking she's "cool again." TL;DR (AKA a summary of this extremely long post that I bet most people don't want to read): Pearl thought that the only thing separating her from tools like Lapis was her ability to protect Rose, and by extention, the earth and humans. Garnet went from not listening to the haters to ignoring everyone who came from the same world as the haters. She also doesn't want her friends to die. Amethyst wanted to recapture Lapis so she wouldn't have to be reminded of how bad she feels about what the CGs did to her. She also tends to follow Garnet's lead.