As has been described by housemates, Estelle is the house scapegoat. She is on the outer and a lot of the house mates like to bitch about people. Being on the outer made it open season for Estelle as no one will get upset, opening up as someone they could all in common bitch about. Not small bitch sessions between two people. So it allowed some bonding as it was something in common. People can bond through bitching and as people formed better friendships, it was almost a guilt free bitch. Estelle being on the outer increased her potential for being a target.
Estelle is also someone who doesn't have to be friends with everyone. She was content kind of doing her thing. Which didn't sit well with the others who are quite clingy to each other. Which ironically is what they labelled Estelle when she met someone she could be friends with and became friends. Estelle was happy being friendly and moving around the group. Not necessarily forming "special bonds." She was just a different sort of person.
The Ava situation dramatically increased problems some house mates had with their disliked Estelle. It seems that in many house mates minds they assumed Estelle didn't belong and would be gone soon and so were not really concerned about being nice or getting to know her. Part of the bitching and meanness was also possibly being used as a way of signalling to each other, "lets nominate Estelle." They assumed they'd succeed and before long she'd just be in the "weird corner" by herself until being promptly booted form the house. However that wasn't happening. Which also lead to some frustration about the lack of control they have. Hence the constant renominating of her. They can't face the fact they aren't in control and the one person they assumed to go hasn't gone.
So this is going on and someone new came into the house and preferred Estelle to them. It kind of raised alarms for many in the house. After all they are so wonderful and she's the freak. Why would anyone chose Estelle over them? It really rattled a lot of their egos and as a result they then bitched even more about Estelle.
Ava was new and pretty and they were simply jealous Ava preferred Estelle. All the talk about separating the two was purely jealousy. They couldn't imagine how anyone could chose Estelle over them. So clearly Estelle was doing something wrong, as they think they are so wonderful and fun. Or at least she was for the sake of bitching and taking out their frustrations. Also one has to assume that the talk about separating Estelle and Ava was part of a way of signalling to nominate Estelle. Who then got 19 nomination points.
None of the housemates besides Josh even really like Ava, yet they are still pissed off Ava chose Estelle over them. This kind increased when initially Sam seemed chummy with Estelle. However that cooled off. It was just the new person thing. He's now settling in. Estelle isn't being clingy at all. As they all were, Estelle was excited about the new house mate. They had their ego's worried for a second they might come off second to Estelle again and so the bitching blaming Estelle continued.
She's still now just the target for their on going frustrations.
With someone like Stacey, we haven't seen anything to her besides her "Act" and her being mean and bitchy. The longer you're in the house, the closer you become to people and the harder to bitch unless there's real issues. Bitching about Estelle has become the thing to do, it's hard to shake and those underlying frustrations. Which are nothing to do with Estelle are still lingering.