People don't really feel "fine about death" but more like "being alive feels worse than death".
There is almost always some thing in such a person's life that is causing such feelings. Even if someone thinks the world is better off without them, it's caused by how they "perceive" their impact on the world, which can be caused by the way other people interact with them.
Here is the tutorial: https://youtube.com/watch?v=Fd7uhYXCBqY