Wow, I just have to say if my husband came home with a "surprise" living creature (from a pet shop, not even a dire situation!), I would wring his neck. And while I'm sure he did it with the best intentions of making you happy, it was an extremely poorly though out situation to put you in. Now you have this young bird, and while I understand that you are considering getting rid of her, also consider how many parrots (especially cockatoos) end up in avian shelters because of of inexperienced, neglectful owners. She is still a baby who's not been trained. She doesn't know (at this point) that screaming is inappropriate. And since you didn't expect/want her, you have also probably been making the problem worse by not giving her as much attention. You obviously have one well adjusted bird, I'm sure you can have a second with a little effort. Plus, your other bird may really appreciate a friend. And if you give it some time and she's really just not working out, plenty of people would take a 2-3 year old bird.
Also, I grew up with a goffin cokatoo and 2 amazons my parents had years before they had me. The goffin was relatively quiet (for a parrot), he only screeched around the time my dad got home. And while he always was the most mischievous, he was still generally well behaved. I think cockatoos attract inexperienced bird owners, and when they aren't well trained, they can be terrors and that's how they're portrayed. I also think they just aren't as suited of a bird in general to be in a domestic environment, for whatever reason. However, plenty of people have had their cockatoo 20+ years and wouldn't ever give their bird up. An animal is only going to behave the way you train it to behave.