I have to bet you have a passion in this world, but you just haven't found it yet. I'm going through this right now. I'm 30 and I've been going through this since I was 12. That's not to say that its never changed or gotten better or worse, I've just had to keep searching for what's really my passion, what makes me tick, whats that thing that i can do that makes me feel content, maybe even happy, almost effortlessly.
For what its worth, I'll share my experience. I hope it helps, but our experiences are going to be so far from shared that I hope you understand this isn't the formula for success you might be looking for. I haven't found that yet, that step by step guide to an easy happy existence. I'm not really looking for it anymore.
Growing up I was kinda forced into the things that I spent most my time on. School, sports, irish music, and I'm sure some other stuff. These are all things i liked and still do, and was decent to great at, but I didn't love to do any of them. And i realize now that i was pushed into those activities so hard because they were really someone elses passion and they wanted me to excell in them too (dad-sports, brother/mom-music). And despite how good i was or hard i tried or satisfaction i got from them, i felt some resent for being pushed into them. They became anything but fufilling or effortless.
But I'd be home and disassemble TVs, lawnmowers, a broken jacuzzi pump, etc. Into their smallest component parts and put them back together so they'd work (usually) again. This was as a 13ish year old. I loved it. I had to know how everything worked. If I had a quiet minute with a screwdriver and something with screws I'd turn that minute into 6 hours and honestly wonder where the time went.
That's all great and wonderful, but I would love for it to have lasted my life, knowing I had one definable hobbie. But it too kind of eventually lost its luster. Partly because I got in so much shit for taking things apart. Partly because I kinda grew out of it (I mean I still like taking things apart but I'm not driven to it). But ive found other pusuits. Other things that just soaked my interest like a sponge. Since then I've had times where I needed to know everything about beer and my stomach needed to be the Noah's Ark of beer. All the beers of the world marching 2 by 2 into my mouth. I've gotten into drawing and spent hours penciling my own shitty 30% complete comic book that nobody's ever seen but that I loved drawing. I've gone through photography, world of Warcraft, driving around, cycling, eating, fuck I can't remember them all.
I guess my point is this, in all those things I did that aren't part of my job, or produce any tangible thing, or what some people would tell me is a productive use of my time, I found fleeting moments of passion, satisfaction, happiness, pride, feeling of being capable. And those moments didn't last, and so far neither have the hobbies. I've spent hours beyond hours feeling what I read you writing. From months to years before finding a new hobby after the last hobby ran its natural course. But I realized at some point, the fact I can feel moments like that is proof to myself I am capable of feeling good, happy, content, etc. Maybe I just havent found the one thing I'll never get sick of. What I've learned is that any of my passing hobbies I've enjoyed the most had some stuff in common. They were mine: nobody encouraged it, whatever drove me to start came from some curiosity within myself. There was the opportunity for research: I devour information vigorously, whether I retain it is another issue. They were usually best enjoyed alone: I could involve others and did sometimes and loved it, but I wouldnt really find that "my own little world" experience unless I was, you know, on my own.
Actually for me that one thing that has stood the test of time is the beer thing. I love beer. But its also possibly a destructive hobby. Thanks Captain Obvious. Okay I'll wrap this little hallmark moment with: learn to recognize when behaviors are getting destructive and deal with them early.
What I read in your writing sounds familiar enough to me that I feel comfortable saying this too shall pass. It really helped me in so many ways when I could confidently tell myself that the depression and boredom were entirely valid feelings, that I have empirically proven to myself that I am capable of over coming them as feelings if only sporadically so far, and that both of those things are okay especially when im im the depths of it. I need to let time march on until my next endeavor and I march on too in the least destructive way possible.
I hope this can help you or someone. Believe me, I get it that it might just be words on the page, that's okay. It doesn't mean I'm doing it wrong or you are, it means you're you, I'm me, this is one in 6.2 billion peoples experience, familiar as it might sound. I hope you find that spark, I think its out there for you.