To
decay. However, in slangish terms: to be
beaten down, reduced or
diminished by an event or place that has made a negative effect on your life. This may have affected your finances, health, social life or any number of other factors important to you.
I can't stand working here, it sucks so bad. I've been going
downhill ever since I've been here. This job is making me rot.
I've
rotted away in university. My school years of constant studying and no life, year after year, have ruined my life.