We talk to the person's family and friends and we watch their behaviour. Sometimes they confide in us. At the coffee shop that I bought, at one point, someone started crying as he was petting one of our cats. He let it out. He was having suicidal thoughts. I chatted with him and told him what I had experienced in the forces. I told him that I had also had suicidal thoughts. Eventually, I was able to lift his spirits a little. However, family and friends really need to listen to the person.
It's very easy for the military to hide the situation from people. It is not talked about. They say it is not suicide or that the person committed suicide for personal reasons, not for reasons related to the forces.