How do you handle cheap clients?

I am quite embarrassed to write this, but I don't know where else to go. Let me first assure you that I KNOW I'm a sore loser, so you don't need to waste your time rubbing that on me. I have been a sore loser throughout my entire life. Bullied growing up, no good grades, and no college education. The only saving grace is that I can do computer stuff and even some programming.

The fact is this; I hate my freelancing gig. Nearly all my clients are a cheapskate, but I need money, and they pay. What should I do to get out of this vicious cycle?

They pay and say they need me to stick around, but my client base as a whole only pay barely enough for me to survive (roughly around $24,000/year). They often tell me how they could always do it themselves using Squarespace, Wix, etc. all the usual visual web builder but need me to build something that is a little more customized than those solutions. I usually have two to three clients every month, each paying no more than $800 per project, and they all ask me to put together a site made of well over 30~40 pages which include tons of image editing as well as content editing. I work from 7 am until past 11 pm. Never been married, and no family to feed. I have no life.

You might say, "Why not just find another job and be done with it??" But, I'm an old dog in my mid 50's, and nobody wants to hire me because of age. I can do PHP, MySQL, Perl, JavaScript and I can build a simple database-driven site from scratch. I applied for well over 200 positions in the past year, and nobody wants me because I'm either not good enough or too old to be in the industry. I tried other fields like customer support, sales and marketing, you name it, just as much, to no avail. The only place I might be able to work is a local grocery store packing bags at this point if I quit freelancing. I still make more than that right now, so I don't want to resort to that kind of option. What should I do then? Maybe panhandling? (SIGH)