Is the money spent on you for taking care of your father-in-law and mother-in-law permissible in Islamic law, especially since your heart is not at ease with taking it?

There is no harm in taking the aid money disbursed by the government, whether it is Muslim or non-Muslim, to citizens, residents, or refugees, as long as the conditions for the aid apply to the recipient. It is lawful money, Allah willing. It must not lead to neglecting an obligation or committing a forbidden act, and it must be taken through official channels without deception.