Is there a reward for a wife's patience in the face of her husband's humiliation, beatings, and insults?

If what you have mentioned is true—that your husband insults you and beats you severely—then he is ill-treating you, aggressing against you, and is unjust. Allah Almighty has commanded good treatment of wives, and the Prophet, peace and blessings be upon him, enjoined good treatment of women. If you have committed a sin, then repent to Allah Almighty, for sins can be a cause of calamities, but a calamity can also be a test. If your husband beat you merely for reminding him and urging him to attend the Eid prayer with the Muslims, then he responded to good with evil, and this is ignoble. We advise you to be patient with him and to counsel him kindly, and to seek help from some righteous people, hoping that Allah may make them a means for his guidance, especially concerning the obligatory prayers which are the pillar of Islam. The Eid prayer is a confirmed Sunnah according to the most preponderant opinion, and a Muslim should not fail to attend it, for the Prophet, peace and blessings be upon him, encouraged attendance.