The group are returning with new LP 'Inflorescent' following an eight-year break and the 35-year-old frontman admitted his battle with anxiety meant they had to "step away" from the spotlight until he'd overcome his struggles.
He said: "We had to step away from music because the thought of playing live filled me with dread. I wasn't aware of the good things about being in this band.
"All I could think was that we were about to get booed off stage. And I'd got into the habit of needing a drink to get on stage...
"I didn't think we'd ever make an album again.
"The shows we've played since we've come back have been brilliant."
Ed recalled being gripped by panic attacks while he and bandmates Edd Gibson and Jack Savidge were on the road promoting their 2011 LP 'Pala'.
He told The Sun newspaper: "Panic attacks started during the second part of the tour. I remember being in Toronto when it kicked in. I was on the tour bus and everything shut down. I didn't know what was going on. It was weird.
"We did three shows at Brixton Academy (in London). I walked on stage and straight away had a feeling of dread. I was hiding away, thinking, 'Oh God, I've got to do this again'.
"It wasn't until a year later when I realised what a big thing it was. I burst into tears and said, "We played three sold-out nights at Brixton Academy -- that's f***ing amazing'!"
The 'Skeleton Boy' singer turned to a therapist which was a huge help, but it still took him some time to process what had happened to him.
He said: "Therapy helped and I started to see the signs -- but it wasn't a case of getting help and suddenly everything was fine.
"As well as dealing with my anxiety, it took a lot of time to gain perspective of what this is all about and why we are doing this. That took quite a few years."
Ed's problems began by his doubts over how long the group could sustain their success after their self-titled debut album received widespread critical acclaim and even a nomination for the 2009 Mercury Prize.
He explained: "The success and attention we had was amazing. They were fun times. But at the back of my mind was the idea that this could be the last time we ever do this -- so I'd start indulging and going out getting wasted all the time.
"Then I'd wonder why the next day I didn't sound so great. Of course it was because I'd been up until 4am.
"This kept happening until I freaked out. The self-doubt came from that and I worried I wasn't a great performer.
"Then the anxiety got out of control. I've always been stupidly over-critical about what I do. I'm a perfectionist, I guess, so I'm never going to be satisfied."