This daf discusses a case of divorce.
One man had a very hard time with his wife. She was somewhat unbalanced and he really did not want to remain married to her. Yet, every time he broached the subject of divorce, she threatened to commit suicide. He wondered if this was reason enough to force him to refrain from divorcing.
When this question was presented to Rav Moshe Feinstein, he ruled as follows: “You may not divorce her. If she is placed in a mental institution, where she will be safe from harming herself, we can discuss the possibility of setting up a letter from one hundred rabbis permitting you to marry a second wife.”
After some time, this man called again. “She is feeling somewhat better and there is a much smaller chance of her actually harming herself. Can I divorce her now?”
Rav Moshe prohibited doing so. “As long as there is a credible danger for her, it is forbidden to divorce her. The Sifri writes that one should not send a yefas to’ar away if she becomes sick. Instead, he should wait until she recovers. It concludes that one should certainly be as careful regarding a daughter of Klal Yisroel who is holy and pure. If this is the halacha regarding a regular sick woman, surely we must extend the same sensitivity to a woman who is mentally ill, especially since this could actually endanger her life!” (heard from Rav Yisroel Belsky).