Hi there,
I'm just chiming in here to express what my personal experience was - hopefully to help you to go a bit easier on yourself and not be too harsh on yourself about the problems you're facing.
Basically, my mid-twenties were the worst time of my life.
This. And I'm 50 now, with a lot more time to look back on.
Like OP, I was a pretty accomplished 25-year-old who felt and was treated much older than I really was.
But -- a 16-year-old can be a really mature and wise adolescent, and still be going through all the changes and troubles of adolescence. Basically, your 20s can be an incredibly difficult time, no matter how sensible and mature you are. They are powerful, overwhelming, emotional, intense. You are still -- not growing up, exactly, but sort of solidifying and forming yourself, and very vulnerable to the world and its expectations. My 20s were fraught with emotional distress, health issues, family issues, and a general aimlessness. I accomplished my lifelong goal, and it turned out to be a bust, so I had no idea what to do next.
I wandered through lots of jobs in software documentation, still not knowing what I wanted to do. A few years ago, I realized my love of video games could actually lead me to a career, so I moved in that direction. I'm now a technical writer documenting internal tools at a video game company, and I couldn't be happier, even though I never would have envisioned this job in my 20s.
Also -- some people just don't have passions, despite that being the current byword. It's okay if you don't, if you're not sure what you want to do, if nothing really calls to you. It's also okay if you do. Finding something to do that you like, or even can tolerate, can be enough, until you're FI and can make your own rules.
I realize "it gets better" may sound trite, but it's true. I was born old. But in many ways, I'm getting more settled, happier, and younger all the time. :)