Burnouts often happen to passionate people who love their work. There are hard limits that conscious part of the mind simply ignores, with laser/tubular focus on whatever is the drive.
For example nurses (both male and female) during WWI - worked themselves to mental breakdowns because there was endless stream of properly suffering people to help or even save. One can't have much more noble goal. Yet hard burnouts kept happening.
I don't want to sound all gloomy since I know nothing about your situation. Just listen to your body and mind, it keeps telling things in subtle ways, not a good idea to ignore that.
For example nurses (both male and female) during WWI - worked themselves to mental breakdowns because there was endless stream of properly suffering people to help or even save. One can't have much more noble goal. Yet hard burnouts kept happening.
I don't want to sound all gloomy since I know nothing about your situation. Just listen to your body and mind, it keeps telling things in subtle ways, not a good idea to ignore that.