When another person commits suicide or kill themselves for example, many people are surprise of such action or event.
That we sleep in the same house(closeness) does not mean we will always know what another person is going through on the inside.
Another thing I have personally discovered in life is that, each of us choose who to trust or at least lean on over life issues. In the eyes of another person, such choice is a wrong choice, but we must respect choices of people.
It is popular to hide issues whether good or bad experiences, though most times, we prefer/decide to hide the good news or experience from another person because of the perception we have towards them. Yes, you are right, it is your decision.
Some two days ago, I read about a man that was rescued by security agents while trying to jump into the lagoon to take his life over sickness that have rendered him useless for several years. If not for the quick response of the rescuers, the man would have been dead by now.
What majorly causes idea of committing suicide is depression. Depression is being in a state of perpetual sadness, inactivity, difficulty in thinking and concentration, a feeling of lowness in spirit.
It is painful to loss people to suicide, but it is also popular and human to hide life issues from closed ones because we choose not to lean on them.
To avoid suicide attempt, people should be kept engaged, carried along, motivated and inspired.