From what I see is that she just needs a break especially from DSP. The company has been holding her back probably, because (based on the articles and comments I've read) she wants to pursue a solo career without DSP.
With all the things she has done, I don't think she would give up on singing or dancing or even for Kara that easily. She fought for Kara for six years, she didn't give up during the first year of Kara (when their popularity was just at the minimum level) and she was only 16 then. She even left America, her hometown, to pursue her dreams. After all the comments by antis, media and many others, she never gave up on Kara (neither did the other Kara5 members).
Let's just hope for the best and don't give up on Nicole or for the whole Kara5 members.
Kara never gave up, they try their best to improve themselves every year, every comebacks to show their love for their dreams and also their love for Kamilias. Such is the beauty of Kara and I am proud to be a Kamilia. They have taught me a lot of things.