Best thing to do I've found is start small. If you set too huge of a goal it might seem too overwhelming and you're more likely to give up, especially with depression involved.

Do you like motorcycling and art still? Go for a bike ride, or if you no longer have one make it a long-term goal to get one again. Perhaps settle for a regular bicycle if affording a motorcycle is out of the question for too long. A bit rusty on the art? Practice! Set a small goal of doing one basic sketch or low-detailed painting (I don't know what medium you use for an exact example). Maybe even try a medium you haven't tried yet.

A purpose is much more personal, so that one I think you need to ponder yourself.

I've not been here in a while so this is the first of your posts I've read, so apologies if I'm missing key details.