A priest who has dealt with over 20 suicides will next week launch a book calling for a radical rethink on how society treats those who try to kill themselves and the families of those who take their own lives.

Fr Aidan Troy from Bray, a former parish priest in North Belfast, says the shame and stigma still surrounding suicide in Ireland must be banished forever. On one occasion, Troy climbed the scaffolding in Ardoyne's Holy Cross Church to try in vain to rescue a young man hanging there.

"Once, those who killed themselves weren't even buried in consecrated ground. It was believed that anyone taking their own life went to hell," Troy said.

"While the situation has progressed, we must ensure that the stigma surrounding suicide has completely gone."

Out of the shadow, responding to suicide, will be launched in Belfast on 1 December. Troy said that priests, police, and medical staff are walking into a minefield when dealing with suicide: "The most important thing is to listen to the families left behind.

"We must have hearts as wide as the ocean to deal with these fragile, vulnerable people. They must not be allowed to feel ashamed, to worry 'Have we been bad parents?' 'Did we neglect our child?', 'Why didn't they confide in us?' In every suicide, the person who kills themselves takes their secret to the grave."

Rather than preach at someone who has unsuccessfully tried to kill themselves, society must hear their story, Troy said: "I doubt that tough love, saying 'Catch yourself on', works. We must encourage those who have attempted suicide to be brutally honest about why they did it – to open up their pain."

Troy, who was last year moved from Ardoyne to Paris, said he had been deeply affected by suicide cases: "I was inspired by how families coped and by those people who had unsuccessfully attempted suicide, then came out of the shadows and found light."