What you and professionals consider an "impulsive decision," many depressive types have been considering or have considered but never told anybody for a long time. It only seems impulsive to you because it appears to be random. If anybody has any understanding of human psyche when they're depressed, they would know it's something you plan but play pretend to others so they don't suspect you need to be "locked up for your own good," as what tends to happen to people who try to seek help.

Mental health problems don't persist simply because people can easily buy guns and kill themselves. They continue because people are afraid their going to have their liberties taken away simply because they want help.