Yevamot 116B

איכא בינייהו דארגיל הוא קטטה.

The practical difference between them is in a case where he initiated the quarrel. In this situation there is no concern that she might knowingly lie, as she loves him. However, due to the quarrel between them she might not be meticulous in her investigations.

איבעיא להו: עד אחד בקטטה, מהו? מאי טעמא דעד אחד מהימן: משום דמילתא דעבידא לאיגלויי לא משקר ⁠— הכא נמי לא משקר, או דלמא: טעמא דעד אחד מהימן משום דהיא דייקא ומינסבא, והכא, כיון דאית ליה קטטה, לא דייקא ומינסבא? תיקו.

§ A dilemma was raised before the rabbis: If there was one witness who testified that the husband died, in a case that involved a quarrel between them, what is the halakha? The Talmud explains the different sides of this dilemma: What is the reason that one witness is deemed credible? Is it because it is a matter that is likely to be revealed, and one does not lie in a case of this kind? Here too, one witness would not lie. Or perhaps the reason that one witness is deemed credible is because she herself is exacting in her investigation before she marries again. And here, since there is a quarrel between them, she is not exacting in her investigation before she marries again, despite the testimony of the witness. The Talmud comments: The question should stand unresolved.

רבי יהודה אומר לעולם אינה וכו׳. תניא, אמרו לו לרבי יהודה: לדבריך, פקחת ⁠— תנשא, שוטה ⁠— לא תנשא?! אלא, אחת זו ואחת זו תנשא.

§ The Mishnah taught that R' Yehuda says that a wife is never deemed credible when she testifies that her husband died, unless she came crying and her clothing was torn, while the Rabbis say she may remarry in any case. It is taught in a baraita: The Rabbis said to R' Yehuda: According to your statement, a crafty woman who knows how to deceive will come with torn clothes crying, and it will be permitted for her to marry. However, a foolish woman who does not know how to deceive will not be permitted to marry. Is this a fair outcome? Rather, both this woman and that woman may marry.