Depression is rampant amongst the witnesses, and even those who have left the organisation but can't find 'their way' so to speak. It's really sad. And what I've found over the years is that out of a congregation full of elders, only 1 if you're lucky, understands mental illness. Most dismiss it. Others don't even try to alleviate the situation. They think that going to meetings and being on field service will be a miracle cure all. It becomes a vicious cycle where you're told to do more in Jehovah's service, but you can't, so become more depressed. I've seen it happen many times.
I've noticed too that seeking professional help is discouraged by the brothers. Their take is that the psychologist or psychiatrist is 'worldly', therefore will only offer guidance that goes against bible principles. Instead they suggest more prayer, more service and that Jehovah will sustain you. Easier said that done. I know one person personally who left the organisation purely because he was depressed and fed up with being told to 'do more', when clearly he was at his limits. Since being out, he's much happier and content within himself.