The victim should have the right to end his life, if he wants. But I think it would be a great mistake. However bad life may seem, there is always something you can do, and succeed at. While there's life, there is hope.
I decided, very early on, just to accept life unconditionally; I never expected it to do anything special for me, yet I seemed to accomplish far more than I had ever hoped. Most of the time it just happened to me without my ever seeking it.