I am also scared of failure. Nobody should have to resort to methods that could fail in the first place, we all deserve the option of a reliable peaceful exit. I think in my case, I will eventually reach the point of desperation where I cannot take it anymore, and only then will I be able to go through with it. It will just be a feeling that I have, that I know it is time to leave. I wish you the best, whatever happens, I hope you find the peace you are looking for.