I personally think that Rarity was not treating her friends badly. I mean, she WAS, but only because of the fact that she was doing what she thought was the right thing. Suri got into Rarity's head that she didn't need friends, and that it was "everypony for themselves." You can't blame Rarity for that.
AJ on the other hand, or hoof, so to speak, was just being plain RUDE. Taking it out on Fluttershy that she wanted to help the bats, and the apple farm. She was in the right. Twilight, the "master of friendship," "Princess Friendship Master," sided with Applejack. I mean, Pinkie was doing her thing, peer pressure, and Rarity is a girly-girl who can't stand the filth. Dash adores her cider. That leaves Twilight. I think-- no I know, that Twi's favorite mane six friend is Jack. They are close. That doesn't mean that Flutters should be ignored and taken advantage of. Her kindness is a virtue, not a hack source.
That's my opinion