Is there anything of importance keeping you in Boston?

If not, I would purchase a one way Greyhound bus ticket and leave. I would go some place with a lower cost of living. If you moved to one of the southern states (Oklahoma, Arkansas, Texas, ETC), or a suburban area where cost of living is low (excluding some of the bigger Texas cities like Austin, Huston), you could easily afford an apartment. I currently live in the south and my studio apt. that I stay in is $500 a month with water included and electric costs me around $60 a month on average which is affordable in an SSDI budget.

You could additionally find a room mate to split costs. There are a number of room mate matching services to help you find somebody that you're compatible with that you could find via a Google search.

Also, if you have a plasma center near you and are able to become a regular donor, you could earn an extra $300-400 a month if you are willing to donate 8 times per month. While this isn't the most ideal way to earn extra money, it is honest and helps people, plus it doesn't mess with your SSDI and it is easy to become a donor so long as you don't have a number of physical health complications.

There are ways out of your situation. Are you willing to take action?