It's 'lonely at the top'. [=powerful and successful people often have few friends]
He was/felt 'lonely' without his wife and children.
the 'lonely hearts' section of the newspaper
(..) But he's really nice, and... I could sort of use someone to talk to... who also talks back. The thing is... I'm sort of lonely... and the past six months have been really hard on me. So what I need is... I need to know that it's okay with you if I go out with him. (..)2006 TvShow: Desperate Housewives Title: Listen to the Rain on the Roof Season: 3 Episode 1