How can my MIL apply for financial assistance/support to continue with the care she requires?

My mother-in law is a widowed spouse of a World War II veteran who recently had a stroke and now needs assistance with daily needs. She currently has an aid tending to her at her home, after spending 6 weeks in a rehab facility, but Medicare will cease providing coverage very shortly. How can she apply for financial assistance/support to continue with the care she requires? Thank you for your guidance.