Unfortunately, people get into thinking in this idealistic fashion about a lot of interpersonal relationships with anything alive, be it their pets or their lovers or friends.
Thats why people are so unhappy. Perfection does not exist. That is step one to overcoming this sort of 'well I got the wrong pet because she does everything wrong and has XYZ pages one through 10 of negative qualities'. Reality is Nika probably has some really good qualities that you are overlooking because you are so focused on what she is lacking from your 'my ideal bird' list. As a dear old flame of mine once said to me, 'Are you willing to fold the hand you have, for the POSSIBILITY of a better one?'
Your boyfriend, may be for example sweet and kind, but he could be lacking in the physical attraction department. OR he could be the most attractive person out there, but in return be irresponsible and a jerk.
Your pet may not be the coolest, smartest or most interactive BUT in return has other qualities you would not find in the 'coolest, smartest or most interactive' pet.
If one keeps searching for perfection, one will never be happy because the grass will be always greener somewhere else. Jacko is goofy, cuddly and very affectionate----do I wish she was a flight-trained, non-plucking einstein who I held meaningful conversation with? Sure! But she will never be those things and a bird who was those things would never be what she is or has.
That said, there are ways to maximize the harmony between your bird and you. This will take time, and effort. Much like moving in with someone for the first time, the period of idealization wears off and you begin to focus only on the differences and there is a period of struggle wherein your own wants and needs vs theirs come into play and reality sets in. You will need to set groundrules, compromise and adapt to each other.
If I remember correctly you have had her less than a year yes? The honeymoon phase of 'omg my new bird who will always be my best friend and will talk a ton and be sweet and love me and...' is over, and now you are beginning to see Nika differently. Its not that she has changed, but she is no longer the physical manifestation of your real-world fantasy (wherein you transfer all your hopes and dreams of your ideal pet bird onto her and stop seeing her for herself).
The first year or two with Jacko was HELL---not because she was a bad bird, but because I lacked the skills and knowledge to communicate with her. Plus, she didn't know me, I was not familiar with her and neither of us had a clue on how to get what we wanted from each other or how to live together. There was no trust and no familiarity. Now---we're like old friends. I know her very well and how to deal with her. She knows the same. We both know how to live with each other and get what we need or want without driving each other crazy.
Its the same with relationships with people.
Now---that said---could it be possible long-term that you guys are not compatible? Yes.
But at this stage I would keep the fact that the rosy-coloured glasses are coming off in mind. It might seem like the grass is greener (or that other birds are better) but that 'sweet baby bird who never bit and loved everyone just like I wanted' could very well end up like this too. Don't go chasing after the fantasy of perfection and forsake what you have. Because EVERY BIRD will go through this stage, and it will be difficult.
Key is to have patience, communication, ground rules, a game plan to deal with problems and keep your perceptions in check. There is a reason she is doing what she is doing---do NOT just label her a 'bad bird' and abandon her---things can be worked on. Also keep in mind her previous owner had her during her easy baby years---and got rid of her as she started to mature (ie when stuff got difficult). SO its probably not 100% true she never bit---it probably means 'she never bit until overnight she just turned into a monster! she hates me now so she has to go!'
Hang in there!
