Aslan frontman Christy Dignam felt so low during cancer treatment, he considered taking his own life.
But the singer said that the imminent birth of his grandchild and the support of his daughter, Kiera, had got him through his darkest days.
He also revealed that Aslan would never tour again after their show in the O2 next summer, but then told how he planned to launch a solo career.
Christy, diagnosed with a rare form of cancer last year, battled depression after six months of gruelling chemotherapy.
It was so bad that after he was diagnosed, doctors warned his devastated wife that he could be facing the end.
They told her: "If there's anything Christy wants to do, he should do it now because he might not have much time left."
"The chemo made me so depressed I wanted to kill myself," Christy said. "I had no idea what I was getting into."
He also explained how without the invaluable support of his family during that difficult time, he may not have made it.
Last summer the unwell singer bravely walked his daughter Kiera down the aisle for her wedding to the musician Darren Moran.
Christy said it was a key moment on the road to recovery and he thanked his daughter, who is expecting a baby in the coming weeks, for helping him overcome his depression.
He said: "What really got me through was wanting to be around for Kiera and to see the baby she was having."
Christy got good news from his doctors last month when they told him his treatment was working, but he knows better than to be complacent.
"(The chemotherapy) worked because the cancer has stopped, but at the same time, I know I have an incurable disease that could come back at any time," the frontman said.
His plans to start a solo career are, he said, "a financial necessity", but for the moment he is just focusing on "building up my strength to play with Aslan again".
But fans of the band, which formed more than 30 years ago were left disappointed after he ruled out tours and indicated that after some one-off shows and a final album, it would end.