Im disabled right now but I have one interest that sux up all my free time and energy. Im pretty unhappy with it right now b/c I'm not making the headway I thought I would with it. But I still love it deep down. Im in a "do or die" phase with it right now.
However I may be a different kind of person. I always wound up having 2 or 3 hobbies/interests at any given pt in time that sucked up all my interest. If you are not the type that has strong curiosity or desire for mastery in whatever areas you take on, or take interest in, then it may be pretty hard to find "purpose".
I never saw this as my "purpose" though. It was just something I liked or did. I still have no purpose in life. I just hope I can master this thing Im currently focused on b/c I am one who seeks mastery in anything I pursue. Often boredome with it may creep in after. I'm sure thats the ADHD in me though.
Even when I became severely depressed and stopped taking interest in things, I took interest in "food sampling"

. I would live to eat every flavor of whatever type of food peeked my interest for that time period.
All of that was to manage boredom. But again its not something I consciously sought out. Its just how my brain works (for better or for worse.)