Check local listservs (you have to join first though) and post that for what you are looking for. I see ads for rooms or apts. almost daily on Tenley and Cleveland Park listservs. Also, call a social services crisis line and tell them what’s going on or NAMI and see if they can link you up with some ideas.
I’ve been in a similar situation and that has helped me a lot more than craigslist which can be overwhelming for both sides of the rental situation.