There is a success hiding in what you call a failure.
You've built a fully working product in a short amount of time. It went pretty much as you have planned it. This speaks volumes to your abilities as a game developer.
You discovered that you are not that great at launching products, marketing, and sales. These are the areas you need to spend a lot of time improving.
It sounds like the plan right now is to get up on your own two feet, financially wise. Get a job that will cover your expenses, so that stress disappears. Start saving up again.
Start learning about sales, marketing, and product launches. They may seem like a second thought to you, but each of these areas is as important as product development.
Another thing to consider is when to quit your job. In general it is said that one should have about six months of living expenses saved up, just in case. This is to cover a situation where you have a job and lose it unexpectedly. That six months of savings will allow you to spend time to find a new job.
To quit your job and self-fund, you need a lot more savings. How much is tough to say. But let's say you give yourself six months to break even in your game venture (no guarantees!), you need to plan an additional X months of savings to find a new job.
The good news is the next time, you possibly will not need to quit your job altogether. You already have a well-built game. Tweak it, redress it, and spend 90% of your time launching and marketing. Perhaps you can do it while you have a job and reduce your financial risk greatly.