Where can I find an AL for my brother who is mentally disabled?

Contact Lutheran Family Services asap. http://www.lfscarolinas.org/what-we-do/adult-residential/

This really sucks. They talk about how every life is sacred - until someone needs services. Then it's all about "personal responsibility." Babies are cute and innocent, but no one cares what happens to old people. End of rant.

How old is your brother? How severe are his disabilities? Does he have a caseworker? Isn't he eligible for Medicaid?

I found a few web sites that you probably know all about, but here they are, just in case.
http://www.ncdhhs.gov/mhddsas/services/housing/index.htm includes a link for aging and adult services.

http://www.nc-ddc.org/resources/north-carolina-disability-information.html

sounds like your in the grey area where hes too crazy for boystown and too much of a boy for crazytown.
dont mind me. my head is just filled with old simpsons episodes -- and grey stuff..

Is it correct that your brother suffers with depression? What are his care needs, more specifically? I'm just wondering what organisations might be able to offer relevant support. Clearly you need something or, as you say, you'll be going under before long too. No family: it's time to find friends you can count on, and I'm hoping people on the forum will have good ideas of where you might start looking for them.