I'm a social worker in the mental health field, and I agree with what you are saying...for most cases. But I am also throwing out there for the sake of discussion that we give people the choice to terminate pregnancies and to die with dignity when they are physically ill, but we think we have the right to force someone to go on living in a (thankfully rare) case like the one being discussed.
A suicide attempt is not always a cry for help. Sometimes it is what it is...a person is tired of living with utter pain and wishes to move on. We allow terminally ill patients this courtesy. We used to force them to live out their last days in pain, with hoses and needles and bedpans being the hallmarks of their last moments. Now we accept their right to die with dignity, and DNRs and living wills are accepted. Why do we think we have the right to "save" someone in a situation like this woman? Can we begin to imagine the agony she is feeling? Ah, but she's not terminally ill, we say. Ah, but in her mind and in her heart, she may well be. We cannot guarantee she will ever feel one ounce better than she does now. Who are we to say that this woman will ever have a single "better day?" Medication and therapy do not always work. Self-medication can lead to even more misery.
I'm not talking about the teenage boy whose girlfriend breaks up with him and who thinks there will never be a better day. I am talking complete and total guilt and pain...pain no doubt every bit as unbearable as terminal cancer...the kind of pain this woman must be feeling.
I've survived the death of one child, and it was the hardest thing I've every had to go through. I dragged on for the sake of my surviving child. Now I have three grandchildren so if, God forbid, something happened to my son I'd drag on for the grandkids. But if something happened to all of them...whoosh...they were gone in an instant...you'd better believe I'd want to follow them. There would be no pills, no therapists, no Biblical passages that would take that pain away.
Which brings me back to my original musing of whether it would be more merciful to "let" someone go be where they want to be rather than force them to live a life of hell on earth.