Is it obligatory for the questioner to return to Morocco to be with his mother, who does not own her own home and is unsettled with his sister, or should he remain in Kuwait?

If you know that your mother wants you to return to her, live with her, and take care of her, then this becomes an obligation upon you. Provision is from Allah, and if you leave what you are doing and turn to honoring and obeying your mother, then Allah will compensate you with something better than what you left, for the Prophet, peace and blessings be upon him, said: "Indeed, you will not give up anything for Allah, the Mighty and Exalted, except that Allah will replace it with something better for you than it."