Don't beat yourself up too much. Doing great stuff takes time, you learned a sh*t load from your last company and next time you can avoid some of the mistakes. As irritating as it is to endure - doing a mediocre job should give you some respite, time to think and the ability save some cash.
Aim to save the maximum humanly possible (reduce spend/be frugal) to give you potential budget or run-way for your next project. Start it while you are employed, work on it when you are at work. Be a terrible employee while more-or-less still looking good... but vest your time in new projects or ideas, or exposing yourself to where you might find them (not pointless crap like most other bad employees do).
Personally, I am in the latter stages of 'medicore job' period after a very similar gig at a fairly similar age (few yrs older). I am hitting 70% net wage savings rate and have one project in-hand progressing reasonably well and a bigger/ambitious project in the works. I spend the majority of my work day working on these projects while still delivering for my job - I really dislike working for someone else but, as a means to an end, this is pretty cushy.
This article seems to use total injury without reference the % of population that participates in (being a pedestrian, driving in a car, riding a bike etc.. )
Very well written - but a particularly poor content and irresponsible use of statistics.
Outsource management to other people/employees with some form of incentive for growing the business on a strictly hands-off basis (3-6 month process) - then use the income stream to enable you to do what the hell you want.