The 'Love Me For a Reason' hitmakers were left distraught when their bandmate died suddenly from an undiagnosed heart condition five years ago aged 33, and they subsequently underwent their ''worst'' ever tour.
Mikey Graham said: ''When he died we were contractually obliged to go on tour. We were grieving hugely and unfortunately the therapy we turned to on that tour was alcohol which was totally the wrong thing to do.''
Ronan added: ''It's the worst tour we've ever done. Alcohol stayed with us for quite some time even after the tour. It became a habit.''
Thankfully the quartet eventually found healthier ways to cope and adjust to their loss.
Keith Duffy said: ''We were using alcohol to numb the pain. I was drinking way too much, upsetting the people I love most and having awful nightmares so I went for bereavement counselling.
''I talked about my grief and the whole drinking problem and I gave up drinking for the whole of 2011. Saying your problems out loud helps you resolve your issues.''
Mikey said: ''I read a lot of self-help books but I don't think it cured me.''
Shane Lynch added to OK! magazine: ''I fixed myself. My mind is very strong but everyone is different.''
Ronan admitted: ''I've had counselling over the years and it's been wonderful.''
All I Want For Christmas is widely regarded as one of the best festive tunes every year
Pearl Jam announced 14 dates in the UK and Europe in June and July 2018.