Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
Dear sister in Islam, thanks a lot for your question which reflects your care to have a clear view of the teachings of Islam. Allah commands Muslims to refer to people of knowledge to get themselves well-acquainted with the teachings of Islam as well as all aspects of life.
As for your question, you have to know that there is no conflict between the wife’s right to have a separate house and the husband being dutiful to his parents. It is incumbent that the husband is dutiful to his parents and takes care of their needs. At the same time, the wife has the right to ask for a separate house and not to live with her in-law brothers in one house.
In response to your question, Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
There is nothing wrong with moving to a separate house if the husband still takes care of his parents, unless they are in such a condition that they need his full-time attention and moving out will jeopardize their health.
If none of the above is the case, then the husband and wife can move to a place close by, where she would have her own free space, and he can still remain in contact with his parents on a regular basis. However, still he should do this after having explained the matter to his parents.
I advise the wife to be patient with her in-laws, and not to react to them angrily or antagonize them. If the wife deals with the situation with wisdom and patience, Allah will give her relief. If, on the other hand, she were to react angrily and antagonize them, then she is going to regret it at a later time. The best approach for her is to treat her husband’s parents as she would treat her own parents. If they are harsh, she should look at the situation as she would treat the harshness of her own parents. Remember, “Allah is with those who are conscious of Him and those who excel in doing good works.” (An-Nahl 16:128)
Almighty Allah knows best.