I do not live by myself. I live with my mom. I do know of a person who lives by herself on SSI. Its hard but doable. She is in a low income apartment (not in a bad part of town). She gets help with her medical. She does ok. She also goes to food banks to help lower her food bill.

To get help you need to go to your local social services office and fill out a few forms and you might get help with food stamps, cash aid, or medical. At the social services office you can also find out where the food banks are. In my town there are non-profits that help low-income people pay their heat bills in the winter (ask at social services if they know of any). You can also fill out a form to get help from PG&E to lower your monthly bill.

Its not easy but you can live alone on SSI. Good luck!