So how do you escape a menial dead-end job when you are older and have no marketable skills?
Get training in something you have aptitude for and there is a market for. Of course, that takes time and money. There is such a thing as age discrimination. On the other hand, some employers might consider an older person to be more reliable.
I've noticed you referring to Dave Ramsey several times through this thread. In reading your posts, I get the impression that you may have missed the majority of his points.
I am a Dave Ramsey Certified Counselor (non-profit/ministry focus). I'd like to attempt to answer the question you've asked.
So how do you escape a menial dead-end job when you are older and have no marketable skills?
1. "Dave says" five years from now, you will be exactly the same person you are today, except for the books you read and the people you meet.
There is no logical reason (barring mental/physical disability) that an adult in America today can't learn a new and marketable skill. Period. Find something you want to do. Go talk to people who make a living in that job field. You will likely find that most folks will gladly tell you the secret their success.
2. Living like no one else doesn't mean self imposed poverty. You mentioned that phrase in one of your posts.
Are you living on a budget? Do you have a defined goal that you are working to achieve? Are you sacrificing short term pleasure for long term gain?
If not, you've missed the point of that phrase. You may be doing the exact opposite in fact.
3. Are you single? None of your posts mentions a spouse. If you're single, why just one job? Other than spending time on line, what else is going on in your world that prohibits you from working more than 40 hrs? Income is your most important wealth building tool.
4. Are you in a good church? One of the blessings of a Christian fellowship are the amazing number of people who can and will help you advance your life. There are Godly people out there praying for God to put someone in their path that they can help. I know this is true, because I practice it.
I'll stop now, I'm sure I'm boring you.