I think the extra 5 classes I'm teaching (along with the famous Table experience) finally caught up today. I just found a website I hope will be promising which focusses on burnout for yoga teachers. People in the helping professions (psychologists, ministers, doctors for sure, etc) have their own type of burnout much of it related to depleting their resources on behalf of others and not having many/any communal places to go for self-renewal. (There is only so much recharging the Bible or other religious texts can offer. Same with medical texts and Dr. Freud).
The thing that may be unique to yoga teachers is physical/body depletion/exhaustion. We use our bodies (more then we realize) in their entirety to teach, even mentally to duplicate routines or poses or deeply 'channel' students, and then to do the necessary movements of life (laundry, gardening, shopping, and for many, children and family - life). Like the other helping professions, we absorb a lot of negative energy from our students - after all, we are there to help them surface and release the resistances that are stored within.
It is all very rewarding, fascinating, 'transporting' with a life of its own. But some days you can hit a wall all of your own. It's subtle and hard to 'own' because we yoga teachers live in 'caregiver heaven' compared with many others. But I'm learning after many years of teaching, it can be complete. There really isn't a community place you can go; maybe this website will be edifying, but ultimately you/I surrender to the depletion and hope renewal/growth/the next planet is around the corner.