I lost my cousin about 6 months ago. Great guy, family guy, great kids doing great in school. He shot himself in the head while his son was in the house (15 year old son). Many of us had spoke to him days before, and no one saw any hint there was any issue. I learned a lot during that time. He was one of the happiest, kindest guys I have ever known.
I learned that judging someone that does that is not quite the right thing to do. Many people that go that route have issues. They are ill people. I had a long discussion with another friend about it when this happened. I had no idea the friend had the same issues. He told me about being bipolar and a little about what it's like. He told me that I couldn't begin to understand it because my brain worked in a normal, rational way. His did not. For me, what was logical, could become illogical to him at times, especially if he did not take his medication. He also told me when that process starts, it's like a switch is flipped and everything you know is rational goes out the window. You don't think you are hurting your family, you think you are helping them, if you are even able to think about the family part of it.
While it's so difficult to understand for so many of us, I think you have to step back and realize, many of these people do have a disease, and it's not black and white for them. Their logic, during that process, is not the same logic we would use or have.
Another cousin of mine called me about 2 months ago. They found his father hanging. He had told his son to go get his passport so they could go overseas together this spring. The day my cousin's passport arrived in the mail, he got the call. Why you'd make plans to travel with your son and then do this, just shows the logic part goes out the window.
I've made it this far in life without ever knowing anyone that's done it. Now, in less than 6 months, I know 2 people. I hope it's something that ends here.