Majella O'Donnell, who broke hearts when she wed Daniel in 2002, has bravely spoken out for the first time about the condition, which has dogged much of her adult life.
In an interview with Ryan Tubridy on 2fm, the 50-year-old mum-of-two spoke frankly of hitting rock bottom during and after the break-up of her marriage in England in the 1990s.
"It is the most dreadful disease you could possibly have. You are in this hole, way, way down and everyone else is at the top. Nobody can do anything for you, absolutely nobody.
"You hear people who have committed suicide and people saying 'why didn't they come to me?'
"But you genuinely believe the world would be much better without you including your children. I did with mine.
"I just thought so many times I'm better out of this. I did consider (suicide) numerous times but I didn't have the guts to go through with it," she said.
Majella, who has just released her first album, told the show that she has experienced depression since her teens and early 20s.
"I haven't been (depressed) since I started taking the anti-depressants. Thanks be to God," she said.
After her marriage to Daniel, she decided to wean herself off only to hit rock bottom again in the middle of a major English tour.
"I found myself with a pair of rosary beads sitting on a toilet at half past four in the morning in a hotel in London rocking back and forth and crying and praying.
"I said 'Please God don't let me go down there again'. Daniel just said then 'Please go back on them and don't ever come off them again'.
"I don't think I will. I think that's it for life," Majella revealed.
Majella, who is mum to Siobhan (23) and Michael (20), admitted she did not want to split from her previous husband.
"I still to this day, much as I absolutely love Daniel and he's a far better partner and person for me, I still wish I was with the father of my children.
"I don't mean that person, just that I was with the father of my children.
"It just complicates everything if there is another person involved but that's life," she said.