I'm a former volunteer for the crisis textline and I sometimes feel the same way, but at the same time I now realize that the fault isn't on me but on the mental health system which we currently have in place. I still volunteer from time to time, helping those in a crisis and following procedures as I should, and even going beyond and doing my best to connect and assist people, but the methods we utilize don't help everyone, it's only for those in a mental crisis and plan to do something drastic based on impulse and not something planned out.
I still feel that one should not CTB based on a short impulse, but that if you analyze all aspects of your life in an unbiased way and feel that death would for one reason or another is better than continuing to live then you should have a right to a dignified death based solely on yourself and no one else.