So why do I still feel so depressed?

I survived a horrible brain injury twice.
I did well in school and went to college and earned a degree.
I found love and got engaged.
I attended again and got a second degree. 
I'm working in the field I wanted to in the speciality that I love.
I have friends and family who love me.
I do the things that I enjoy doing.

I feel hopeless.
I feel worn out.
I am bored with life at only 27.
I feel pessimistic.
I feel depressed.

Does anyone else feel like they've done all the right things, followed all the right steps, and are still depressed?

I know this process takes time but it's hard to feel motivated to continue trying when for almost eleven years nothing I'm doing is helping.