How can Steffy not see the HYPOCRISY!

So today she was arguing with Liam because he didn't agree with her considering the position of CEO, because Quinn, bla bla.
Sure, Liam might have some very valid concerns, and sure, Steffy if pretty shallow to think everything Quinn says or does is about her, but Steffy and Liam had the following exchange;

Liam: "Yes, your grandfather said the words, but they're her words."
Steffy: "I hear your concerns, they're valid and I don't trust her any more than you do, but you're acting like my grandfather can't act or speak for himself and i'm suddenly too gullible to watch my own back....."

OK, so now that this is something Steffy wants, and can benefit directly out of, suddenly Eric is of completely sound mind (in her eyes). What about all the weeks or hand-wringing and plotting- even before Eric had his stroke- about how Eric is seeing Quinn, and he must be senile and losing his mind, and maybe he needs to be committed, and his judgement is so impaired as evidenced by his new relationship that he can't be trusted with the company.
Sheesh. Talk about an about face. Because Eric thinks Steffy can be CEO then now, according to Steffy, he is Fiiiiine. Just forget everything we got ourselves so worked up over.
She is such a selfish, self-entitled hypocrite. That she can't see it is astounding and that the writers don't think that these complete shifts in personality will go unnoticed is equally as astounding.
And no doubt, because for the first time since they are back together Liam disagrees with her, Steffy, being the petulant child she is will get angry, fight with him and no doubt find her way back (accidentally of course) to Wyatt and everyone will blame it on Quinn...