Hey, hang in there. Keep searching. I'm still on the journey. I'm over 40 and recently diagnosed with ADHD and some form of bipolar/manic stuff.

Finally found a good head doc, meds etc. up until this, it was a slow but increasing downward spiral. I just became apathetic....to existence.

At work, I constantly felt imposter syndrome, couldn't stay focused. Any minor mistake felt like the world was ending. At home, minor family drama felt like I was a complete failure as a husband, father and an adult.

Now? Most of all that is fading away. Still a ways to go but hope is in sight. I've began to recognize things that would have put me in a dark place. Now it mostly rolls off me.

So, to answer your question: It feels like every little mistake, insecurity etc is nothing more than a memory of shit that got to me. It's a sorta weird poetic justice. Like seeing a bully get out in their place.

Edit: I'm sure you have but get some blood work done. Hormones, and Vitamin D levels. I've been struggling with vitamin D for a while now. It absolutely will cause issues if too low. It's an "easy" fix with simple supplements. None of this is quick. Takes a few weeks generally to even begin to notice. But in time you should.