I am sorry to read about your situation and experience. Like others, I strongly suggest that you contact whatever Mental Health Services that exist within your local area. This is something you should not have to deal with alone, even IF you could!
There is always the risk of becoming codependent to another's mental illness which can severely affect your own, no matter your good intentions. I am not a "tough love" advocate, but can you honestly provide the appropriate care and support your friend really needs? There are professional, trained people who do that sort of thing...you know, making sure they take their meds and such?
In Australia, we have a service called ARAFMI (Association of Relatives and Friends of the Mentally Ill) which handles such matters with trained counselors, respite services and ongoing support for both the Mentally Ill and their primary caregivers to make the transition into a more sustainable and therapeutic environment for both.
After a short search on the internet, I found this:
https://www.samhsa.gov/homelessness-programs-resources
If you search around, you are bound to find resources for people who have mental illness...who are experiencing homelessness...who have friends at their wits end trying to accommodate them...not only physically but mentally, emotionally... financially...
Over here in Australia, we have Partners In Recovery which is a peer-based support program:
https://www1.health.gov.au/internet/...ent/mental-pir
So now I wear the hat I rarely put on...that of being a qualified social worker...I must go and update my credentials at college again..one day...