Chris Martin was "hard to live with" before he split from Gwyneth Paltrow.
The former couple - who have children Apple, nine, and Moses, eight, together - split last month after 10 years of marriage, and insiders claim the Coldplay frontman's insecurity caused a lot of their problems.
A source told Britain's Grazia magazine: "Chris is very tough on himself and that can be hard to live with. There was a time a few years ago when there were a lot of fights.
"He and Gwyneth had a great life but it was like he couldn't quite see it and couldn't commit to it. There were other issues that sparked off that and, ultimately, they ended up leading very different, very separate lives."
Now they have gone their separate ways, Chris and Gwyneth both want the best for one another.
The source added: "They have both given each other their blessing to move on. I think they both want each other to find love and happiness."
The Magic singer recently admitted his own "issues" had stopped him from being happy.
He said: "If you can't open yourself up, you can't appreciate the wonder inside. So you can be with someone very wonderful, but because of your own issues you cannot let that be celebrated in the right way....
"About two years ago I was a mess really because I can't enjoy the thing that we are good at and I can't enjoy the great things around me because I'm burdened by this - I've got to not blame anyone else and make some changes."
- BANG Showbiz