“I’ve studied medieval literature, and I love my subject, but it feels like a very selfish choi asdfadsf ”

I've studied medieval literature, and I love my subject, but it feels like a very selfish choice. How can I reconcile that passion with the sense that I should be doing something more obviously important and helpful with my life? What is the balance?n* I'm not a very good teacher, so that's probably not the best compromise. Thanks!