An interesting question! I've often thought about what would life be like if this wasn't a viable option. I developed my first suicide "plan" and wrote my first letter as a thirteen-year-old. Since then, it has always been something I've considered an option as my struggles with major depression have been a part of my life for other thirty years now. A friend recently berated me when I shared with them that I feel my cause of death in life has over a 50% chance it will be by suicide versus natural causes. I just don't have hope or excitement about my life/journey anymore. I'm single, lonely as hell, and don't see that all of a sudden changing in the upcoming years, and life is only going to get worse from this point on since I'm well past my prime.
Getting back to the question, I remember sharing a conversation with one of my brothers years back and being amazed by his response. I was in a major depressive episode and we were talking and I asked him out of curiosity, "Have you ever thought of or considered taking your own life." His response was quick and easy, "No, it's never crossed my mind." It was hard for me to comprehend. This has been a thought that has taken space in my brain now for years. During struggles with depression, it's what occupies my mind the majority of the day...planning, fantasizing about doing it to end the pain, etc.
I wonder what percentage of people in our country have never considered suicide or thought about taking their lives? For me, it's a viable option and thought I frequently think about.