Gemara

61b (Mishnah - Beis Shamai): If one forbade Bi'ah with his wife through a vow, up to two weeks he may stay married;

Beis Hillel say, up to one week he may stay married. (Beyond the limit, he must divorce her and pay her Kesuvah.)

Gemara: Beis Shamai learn from Yoledes Nekevah (one who gave birth to a girl), who (is Teme'ah and) may not have Bi'ah for two weeks. Beis Hillel learn from what is common, i.e. Nidah, who is forbidden for one week.

62a - Question (Rabah bar Rav Chanan): (Surely, Beis Hillel would not force one to divorce his wife for a vow above a week if his Onah was infrequent in any case.) Does the Mishnah teach only about idle men and workers?!

Answer (Abaye): No, it applies to everyone.

Question (Rabah): In any case, the Onah of sailors is only once every six months!

Answer (Abaye): One who has Pas b'Salo (bread in his basket) is unlike one without Pas b'Salo. (Without the vow, she had hope that her husband would return early.)

63b (Beraisa): The law of rebellion (one who refuses to have Bi'ah) applies whether she is an Arusah or a Nesu'ah, even if she is Nidah...

Question (R. Chiya bar Yosef): A Nidah may not have Bi'ah! (Why is she considered a rebel?)

Answer (Shmuel): One who has Pas b'Salo is unlike one without Pas b'Salo.

Rishonim

The Rif and Rosh (5:29 and 5:33) bring these Gemaros.

Rif (26a): Rabah thought that Beis Hillel teach only about idle men and workers, whose Onah comes within the week.

Ran (DH Garsinan): Also the Onah of donkey-drivers comes within the week! R. Yonason explains that 'workers' refers even to those who work in a different city, and obviously the same applies to donkey-drivers, whose Onah is also once a week. This is unreasonable (that Rabah could not fathom why Beis Hillel taught a law that applies to most categories). Rashi explains that he refers to workers who work in the city. Rabah thought that Beis Hillel teach only about men whose Onah is more frequent than weekly, for it is unreasonable to make him divorce her for delaying Onah by only one day.

Rif (ibid.): If one has Pas b'Salo, his heart is not hungry. If one has no Pas b'Salo, his heart is hungry. (Even if her husband was not due to return for six months,) since he forbade her with an oath, she is like one without Pas b'Salo, therefore he must divorce her and pay her Kesuvah.

Rosh (ibid.): The Yerushalmi says that we cannot discuss when she rebelled after becoming Nidah. The Torah made the rebellion! Rather, she rebelled before becoming Nidah, and continued to rebel after becoming Nidah. The Gemara asked why the days of Nidah should count towards the four weeks of rebellion. This is difficult. Surely the days of Nidah count, since she began beforehand! The Bavli is more understandable. She is a rebel even though she began while she was a Nidah, for one with Pas b'Salo is unlike one without Pas b'Salo.

Rambam (Hilchos Ishus 14:6): If one forbade Bi'ah with his wife through a vow, up to one week we wait. If it was more than a week, he must divorce her and pay her Kesuvah, or permit his vow. Even if he is a sailor, whose Onah is only once every six months, his vow pained her and caused her to despair.

Rambam (7): If he became sick or weak and cannot have Bi'ah, he waits six months to get healthy, for this is the longest Onah. Past this he needs her permission, or must divorce her.

Rambam (11): The law of Moredes applies even if she is a Nidah who may not have Bi'ah. It is even if he is a sailor, whose Onah is only once every six months/

Magid Mishneh: The Rashba says that this is only if she began to rebel before becoming Nidah. The Yerushalmi says so. The Bavli and the Rambam did not distinguish. The Rambam learned from here that the same applies if he is a sailor. We may also learn from forbidding Bi'ah through a vow.

Tosfos (63b DH Eino): Rebellion applies even to a Nidah, for without the rebellion he had Pas b'Salo. Above, we said that one who one forbade Bi'ah with his wife through a vow remains married for seven days before he must divorce her, just like a Nidah is forbidden for seven days. (I.e. because she can become Nidah, a man never has Pas b'Salo, i.e. assurance that he can have Bi'ah within a week!) Rebellion gets rid of Pas b'Salo more than a vow does, for perhaps the vow can be permitted. A proof of this is that we add to (or subtract from) the Kesuvah for rebellion, but not for a vow.

Poskim

Shulchan Aruch (EH 76:9): If one forbade Bi'ah with his wife through a vow, whether it was Stam (without a set time) or for seven days or more, he remains married for seven days, and then divorces her and pays her Kesuvah. This is even if he is a sailor, whose Onah is only once every six months.

Shulchan Aruch (77:2): The law of rebellion applies even if she is Nidah or sick and cannot have relations.

Rema: We do not distinguish whether she began to rebel before or after becoming sick. Some disagree.

Chelkas Mechokek (18): There is a textual error in the source cited by the Rema. The first opinion should be attributed to Moharam, and the latter to the Ran and Mordechai. I do not know why he did not attribute the first opinion to the Rambam and Rosh, who say so more explicitly than Moharam.

Beis Shmuel (22): The Rema brings the argument regarding when she fell sick. This is a bigger Chidush, for it is not known how long she will be sick, nevertheless the latter opinion requires that she rebelled before becoming sick.

Rema: It is even if her husband is a sailor, whose Onah is once every six months.

Chelkas Mechokek (19): This is clear from the law of a sailor who forbade Bi'ah through a vow. There, Onah was not due to come for six months, nevertheless he must divorce her. Here, if not for her rebellion, he could have decided to return early and make the Onah come earlier! We must say that the case is that he is leaving now and does not intend to return for six months, and she says that she will not have Bi'ah when he returns, just like a Nidah who says that she will not immerse when the time comes.