Never continue in a job you don't enjoy. If you're happy in what you're doing you'll like yourself you'll have inner peace. And if you have that along with physical health you will have had more success than you could possibly have imagined.
Light is meaningful only in relation to darkness and truth presupposes error. It is these mingled opposites which people our life which make it pungent intoxicating. We only exist in terms of this conflict in the zone where black and white clash.