I think a lot of people think doing good things is supposed to feel good, when in reality it's more about piercing the veil. Take getting into shape for example, people often exercise for months before seeing any kind of results. In fact, a lot of time, as your body recompositions by adding muscle, you end up gaining weight. You step on the scale expecting to have lost weight and there is no progress, week after week. You have to stick through the "it sucks" part. Then when you start seeing results and health benefits, it helps your self esteem and makes you want to keep going. I worked out for 3-5 times per week for about 3 months before I started seeing results. And it sucked. It's supposed to.
There are no people out there who start doing something difficult and immediately feel reward, purpose, and fulfillment. You're always going to feel like a moron who doesn't know what they're doing. Being successful means you must be very comfortable with failure and be able to reiterate your efforts until you see results.
I say this as someone who sits in an engineering position who's applicants are expected to have 10-15 years of experience as well as a college degree. I'm a 9 year self taught engineer who runs circles around my colleagues. At this point, I've failed at more things than most people have even attempted.
you're right, but if depression is an ailment, then it's the responsibility of each individual to seek treatment. A lot of people wear depression on their sleeve like a disability.