Does the supplicant deprive herself of the virtue of 'Umrah, or should she travel to perform it again despite her mother-in-law's ill-treatment of her?

Do not deprive yourself of obedience to Allah due to someone's ill-treatment. Instead, fulfill His saying, the Almighty: "Repel evil with that which is best," and His saying: "Nor can a good deed and an evil deed be equal. Repel (evil) with that which is better." Treat her kindly, seeking Allah's pleasure, out of consideration for your husband's rights, and to maintain kinship ties. For the Messenger of Allah, peace and blessings be upon him, said: "If you are as you say, then it is as if you are feeding them hot ashes, and you will continue to have a supporter from Allah against them as long as you remain in that state."