What does this dream mean?

I have the same dream at least twice a month. In this dream, I quit my old job, which is what actually happened. In the dream, however, I start working there again and drop out of my training again, this time earlier. When I wake up, I always feel as bad as I did when I still had to work there. I now have a different employer, and I really like it, even though I had to give up my dream job, which sometimes makes me sad. What could this dream, and especially the constant repetition, mean?