I don't agree that this is Whitneys first misstep. She has been 'telling it like it is' the whole way through and people have let it slide because they thought she was funny. It's only that there is nothing funny about saying 'You are the most selfish person I have ever met' that people are finally sitting up. Just in the past week she went in on Abi telling Abi how Abi feels, because Whitney 'doesn't lie', shutting Abi down and being a witch. I don't like Abi but there was no need. Then there was the remark she made to Scott when he was upset, I can't remember what it was about but she said something like 'maybe there was truth in it', again it was a bitchy comment for no reason and she has done that consistently across the season.
Let's not pretend that this is Whitneys first time being a witch, she hides behind being a tell it like it is person but we all know what that means in real life. Its very easy to 'tell it like it is' it's far harder to keep your mouth shut and just be kind sometimes.