One of the things that they don't tell you about mental illness is that it means you're supposed to be happy with the minimum.
For the longest time, I couldn't figure out why just basic adulting took so much work. Why did other people seem to have it together so much more than me? When did they find the time for all these things like cleaning up their houses? In reality, I deserve a medal for functioning on some basic level. But growing up with the normal expectations of a “gifted” middle-class kid, and my expectations for myself don't necessarily conform to what's actually possible. It's not that they're that high, it's that my capabilities simply aren't what normal people's are.
Accepting this has been a struggle. I don't want to think that where I am now is the most I'll be able to accomplish; I don't want to be on my deathbed and have to content myself with “I was a decent bureaucrat.” But what I'm actually capable of doesn't have any real correlation with what I want.
The obvious answer is to find a passion, something I can do where it doesn't matter whether I'm good or not. This has failed to occur so far, and I'm not sure I should keep waiting. I've been doing the experimenting thing for 20+ years, and it hasn't really borne fruit. Instead, I have to figure out how to be more comfortable in my own skin, and how to accept the realities.
Completely disregard things like "productivity" or "ambition." Your goal should be to create the happiest possible existence for yourself. If you can do this, you will be successful. If this means disregarding work to the maximum possible extent to save mental energy for hobbies or whatever, then so be it.
I'm not quite sure how to separate the two, because for me being happy specifically involves feeling like I'm accomplishing something. I don't necessarily need, say, to have a prestigious job, but I would like to feel some semblance of ... well, accomplishment is the word I keep coming back to.
Adult life is strange. While in school we progress year after year, learn new things, meet new people, I feel like after that things change a lot. Sure, we progress, but it's slow rather than quick. Sometimes we regress a little, sometimes nothing really changes. I guess adult life is just about living how we feel like.