ANSWER:
Some scholars say that this takes her out of the fold of Islam due to willingly abandoning a prayer without a legitimate reason. However, the most authentic opinion is that she is sinful and had committed a major sin but she is not yet Kafir.
She can’t make up any of those prayers as they are gone forever and she will be questioned and tormented for skipping them in her grave and on the day of judgement unless she repents.