Perhaps you mean it in a different sense, but it's not possible to not have the option for life, you can choose not to experience life, you can say the reasons against it are too much for you, but there's never a time when life is no longer an option.
Suicide is what occurs when you don't have the option for life.
When you have a terminal disease, you've entered the state of being in the end of life. You're just choosing how that endgame plays out.
Not everyone has the fortune to die surrounded by the corpses of their enemies.