Mine started when I started working midshift.
I learned how to get by with 2-3 hours of sleep a night and I haven't quite unlearned that yet.
Mine started earlier this year, but got really bad when I started that new job in May. It was so bad that by early last month I was a walking zombie. I was so stressed out that when they offered me a voluntary termination, I took it and walked out. Then I slept for 3 days.