The sad news actually provides a plausible (though not confirmed) explanation for why she lied about the crash (as the police and bus driver confirmed). Her fabricated story of serious injuries may have been her way to be open about the fact that she was expecting to end her life soon, without admitting that she was planning on suicide (with all the possible consequences such an admission would have).
Ms. Giuffre’s family’s announcement specifically blames "the toll of abuse" from "being a lifelong victim of sexual abuse and sex trafficking" for her death. Sadly, it seems that even winning a substantial settlement, as well as a public acknowledgement of her suffering, from her abuser-trafficker’s best-known enabler was not enough to overcome it.
Unfortunately, thanks to that British royal element, I suspect her grieving family will be swamped with unwanted theories regarding the cause of her death, despite their certainty and transparency.