All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
Not every complaint contradicts being content with the Decree of Allah, no matter how many times one complains. As long as the complaint is free from being discontent with the Decree and it has a correct purpose, such as removing harm or asking for one’s right from the person who is obliged to fulfill it; in such cases it is a permissible to complain and there is no harm in it.
It is your right that your husband provides you with an independent dwelling with whom none of his family shares with you. He has no right to force you to live with them in the same house.
The Kuwaiti Fiqh Encyclopedia reads:
“Combining one’s parents and the wife in one dwelling is not permissible (as well as other relatives). Therefore, the wife has the right to refrain from living with any one of them (parents of one’s husband) because being in an independent dwelling where she will feel safe regarding her own self and wealth is her right. No one has the right to force her to live with them, and this is the view of the majority of the jurists of the Hanafi, Shaafi’i and Hanbali Schools of jurisprudence.” [End of quote]
However, if it is difficult for your husband to combine between taking care of his mother and providing you with an independent dwelling, then it is more appropriate, if there is no harm on you, to be patient and seek the reward of being benevolent to your husband and help him be kind and dutiful to his parents.
As for your husband's advice to you about praising Allah, seeking forgiveness and performing acts of obedience to get closer to Allah as much as possible, then it is a useful advice in all cases. Abundantly remembering Allah, seeking His Forgiveness and being keen on getting closer to Him, are means through which one achieves tranquility and success in this worldly life and the Hereafter.
For more benefit, please refer to Fataawa 84608, 253297, 88654, 86132, and 384583.
Allah knows best.