The Social Network star revealed that he went through his fair share of ladies while he tried to work out 'what he wanted'.
The 29-year-old singer turned actor has been with Jessica Biel since 2007. He said that he would rather be in a relationship than play the field.
He told OK, 'There was a time when I had lots of affairs with women. I had to find out what I wanted.
'But basically I prefer being in a relationship. But it's not very easy to have one because I am under constant observation. The only solution to this is to keep mum about it.'
The Cry Me A River singer added that he's a bit of an old romantic and that he can't stand game playing.
He said, 'First of all honesty, no games. And I don't begin a relationship inconsiderately, because I have to build up trust first. Then I devote myself totally. I am very romantic but I want to be able to laugh as well. If I sing about unconditional love I know it first-hand.'