British rocker Chris Martin has spoken candidly about his split from Hollywood superstar Gwyneth Paltrow, describing the delicate personal issues which drove the couple apart.

The celebrity couple confirmed they had separated in March (14), with Paltrow branding the split "conscious uncoupling", and the Coldplay star has now revealed he struggled to "let love in" and "wasn't completely vulnerable", which "caused some problems".

In a frank interview with Radio 1 DJ Zane Lowe, Martin was asked about the breakdown of his marriage, and he replied, "I wouldn't use the word breakdown, this was more a realisation about trying to grow up, basically... 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...

"What changed for me was - I don't want to go through life being scared of it, being scared of love, being scared of rejection, being scared of failure... Up to a certain point in my life I wasn't completely vulnerable and it caused some problems. If you don't let love really in then you can't really give it back."

Martin also reveals he has been struggling both personally and professionally over the last few years: "About two years ago I was a mess really because I can't enjoy the thing that we are good at (the band) 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."

However, the singer insists the band's new album, Ghost Stories, allowed him to be honest about his personal issues using music as an outlet, adding, "What Ghost Story means to me is like you've got to open yourself up to love and if you really do, of course it will be painful at times, but then it will be great at some point... I think in life everyone needs to be broken in some way. I think everyone in their life goes through challenges, whether it's love or money, kids, or illness. You have to really not run away from that stuff. Life throws these colourful challenges at you; what we decided to do on Ghost Stories was to really be honest about it and say, this is what's been happening."

The full interview airs on BBC Radio 1 on Monday evening (28Apr14).