Full question - Was Jane Rochford forced to lie? or did she really hate her husband so much that she made up the incest lie all by herself?
Most historians believe that Jane's testimony regarding Anne and George's alleged incestuous relationship was driven by spite and jealousy, and George Wyatt (son of Thomas Wyatt) also believed this. However, Julia Fox, biographer of Jane, suggests that Jane had a warm friendly relationship with Anne Boleyn and that Jane was frightened by Cromwell and what was happening and that her words were twisted. Fox says:
"Jane Rochford found herself dragged into a maelstrom of intrigue, innuendo and speculation. For when Cromwell sent for Jane, he already had much of what he needed, not only to bring down Anne and her circle, but to make possible the king's marriage to Jane Seymour... The questions to Jane [Rochford] would have come thick and fast... Faced with such relentless, incessant questions, which she had no choice but to answer, Jane would have searched her memory for every tiny incident that occurred to her... [But] Jane had not been quick to tell tales, but she had buckled under the pressure of relentless questioning... And it was her weakness under interrogation that gave her future detractors - happy to find a scapegoat to exonerate the king from the heinous charge of callously killing his innocent wife - the ammunition to maintain that it was her evidence that had fooled Henry and destroyed Anne and George..." (quoted from Wikipedia).
I'm looking forward to reading Julia Fox's book!