to put it simply, while it's still not clear enough what alty's motive actually is, she likes in the side to support maria's love too much she kind of including herself to maria (no longer on the watcher's side). she instead ends up making her going more berserk (she was already unstable because of her trauma). well, alty is a monster. it is understandable she only understand surface-level of human emotion that she was mentioned she was seeking or admiring before. and palinchrome (the one who should be the most in the known about all this) didn't help because he was a simp to alty (dunno why though). maria will be more broken after she comes awaken after her sanity cooling down.
this one unrelated to the story, but IRL you would find this behaviour in people who likes shipping characters. some people indeed crazy but because they can't do anything more they just went crazy in the social media. there is a person who did crime like burning the studio that makes the anime that person thought it was his original idea but the studio ends up not doing what he like in his mind
