I do career consulting (and resume writing) mostly for clients from tech. I think some arrangement where you had multiple forms of income (or potential income) might be a good solution for you. What might that look like?
- Freelance software development - This would give you some control over what types of projects you work on, and you could focus on areas that really interest you. Maybe it would be projects that enable you to learn a new language. You also can typically work from home, and you will be able to balance your time between different work.
- Freelance writing - If your writing is good you can certainly pick up some $$ here and there by writing articles for tech sites. I've done that for tech sites as a writer on career topics, and many of these sites are always seeking new content. The amount of money may not be a game changer, but if you enjoy the work you can probably make this 10% of your overall income.
Personal projects - Perhaps some of them can be monetized and you just haven't come up with the correct concept. Or perhaps you can come up with some ideas for projects that are both interesting and able to be monetized.
Working for yourself is quite motivating. I've done it for several years, and when failure isn't an option you will find ways to stay motivated. I spent 20 years in recruiting before transitioning fully to my current job (resume writing, content writing, career consulting, other freelance writing projects), and I've really enjoyed the change.
Some people aren't cut out for a 9-5. I certainly am not, and it doesn't sound like you are either.