How do you avoid burnout?

If you want to avoid burn out and bear fruit and in your parish,  Jesus is the answer. Jesus and only Jesus. You need to be with him. Go to him constantly in scripture and in the Blessed Sacrament. Make sure that he is the source of your ministry by cultivating a deep interior life of prayer.

Seek first the Kingdom, and the rest will be given you as well. 

Matthew 6:33