Related su Ketubbot 10:4

A wife who said, "My husband died" [and there is no independent verification]—she can either be supported [by her husband's estate] or take her ketubah. [If she said] "My husband divorced me"—she is supported up until [the value of] her ketubah [since she is certainly entitled to her ketubah, whether her husband died or divorced her]. What is the difference between death and divorce [such that she is automatically believed if she said her husband died but not if she said he divorced her]? With death, she is not able to contradict him; but with divorce, she is able to contradict him, for she could say to him: "You divorced me!"