Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
We ask Allah to cure you and bless you with pious offspring.
You have to know that you should not ask your husband to divorce you as long as you are not harmed by staying with him, because it is forbidden to do so.
Tirmizi and Abu Dawud reported that Abu Thawban (Radiya Allahu Anhum) narrated that the Prophet (Sallallahu Alaihi wa Sallam) said: "Any woman who asks for divorce without any reason, the smell of
By not asking for divorce, you are being faithful to your husband who is a good person as he does not wish to divorce you despite the objection of his mother.
With regard to your mother-in-law, you have to be patient with her, and treat her well although she is being rude to you, because she is your sister in Islam, and out of respect to your good husband. You can ask your husband to provide you with a private dwelling separate from the house of his mother. This may be an acceptable and definite solution, Insha Allah. You have to be soft with your husband until he is convinced of this, and let him know that this is a juristic right for the wife. You can also show this fatwa to him. If he refuses, and you are harmed by staying with him, let him know about the harm, and ask him for divorce. If he accepts and directly divorces you, then this is what you wished for. However, if he refuses, then it is permissible for you to pay him an amount of money in exchange of getting a divorce from him.
This is what the Fuqaha call "Al-Khul'u". If again he refuses, and there is an Islamic court of justice, then you can take your matter to the judge so that he can remove the harm from you, hence relieving you from the burden.