Simon Cowell prefers to be alone during 'dark days'

Louis Walsh has revealed that Simon Cowell keeps to himself when he is in a bad mood.

The 'X Factor' UK judge said that the 54-year-old music mogul has "'dark days" like everyone else, but he prefers to spend time alone during that phase, Contactmusic reported.

However, the 61-year-old Irish entertainment manager insisted that they are very close and have an understanding based on trust and "honesty".