Suicide
Everyone is responsible for his life before God who has given it to him.
It is God who remains the sovereign Master of life.
We are obliged to accept life gratefully and preserve it for his honor and the salvation of our souls.
We are stewards, not owners, of the life God has entrusted to us.
It is not ours to dispose of.
Source: Catechism of the Catholic Church (Vatican.va)