So sorry for your situation. You might contact the National Autism Association to find a local chapter in your area and see if they have any ideas or suggestions. Contact the Salvation Army in your area and see what they might offer .... See if there's some sort of helpline at your local newspaper and share your story, perhaps they'd write it up in a holiday related article and readers could donate. Lastly, try using a "crowdfunding" website to see if you can tell your story and get donations. Definitely see the article Free Money 2015 to see a description of the top platforms online for people to share their situation and see if others will help out. Your situation could be perfect for that, especially during the holidays.
Also, there is an excellent website for the disabled and those who care for them. It's updated daily and is pretty good at guiding you to resources, including those in your own zip code. Take a look at this guide to using disability.gov.