The mistake you made, which is one many people make, is to trud along when clearly the math doesn't pan out. If you made $15000 a year for most of your life... then why didn't you adjust your living standards and save money? I made around 20k in dollars a year (although hard to estimate over all those years due to EURUSD being all over the place) and often on benefits for 14k. I thought I was going to "move up" at one point and make more. That never happened, so I adjusted my living standards and started saving money. I didn't just go along and think things were magically going to get better and I would be saved by the circumstances, rather than to prepare for the worst, which is that things are about as good as they are going to get. And that's exactly what happened in my case. The only thing going well for me are investments, but I never got over like minimum wage +10% (which, honestly, is still quite a lot in Europe).
I know this won't really help you now, but it might be handy for people reading this that still have time. The only thing you can do now is do what you should've done 30 years ago, only far more drastic. No fancy Cauliflornia apartment, you are going to have to find a cheaper place that you can afford off $1000 in benefits, or continue working. Continue working would also be smarter in a cheaper area so you are not going to be working until the day you die.
Fortunately, I began saving money beginning with allowance at age 12. I survive today because I have been gifted money over the years by my parents and late grandparents and put most of it in mutual finds in 1995.
Although I do not ask for it, and actually complain about it, my 86 year old mom still gives me $60 a week.
I currently earn about $23,000 a year, and I plan to work until age 70 if i can stay healthy, which is a challenge with diabetes. If I work until age 70, my SSA benefit would then be $1320 a month. Conversely, if I were to retire at age 62, I would get only $750 a month.
I also did not move out of my parents house until I was 34, hence saving much in rent for many years. My main mistake with details beyond the scope of this thread, was that I foolishly tried to succeed in STEM where I did not belong.
I would have much more money today had I dropped out of high school and went straight to work.