When anyone is in pain, all sorts of possibilities cross your mind to escape the pain. However, you would never advise a friend to die to escape pain, as you know that all pain will eventually stop. Do not throw away the rest of your life due to a temporary pain, no matter how severe it is.
There are lots of people who would rush to your aid if they knew you were drowning;equally, they would rush to your aid if they knew you were in danger of dying from something like stress or depression. The illness may try to fool you into thinking you are alone, but the reality is that lots of people want to save your life, just as you would if the positions were reversed.