I don't disagree with you said but several misgivings:
- that's not a classroom teacher's job 9in most subjects anyway) and she could mishandle it, giving rise to student and parental complaints as we have seen!
- some students respond to talking about issues ; for others that's counter productive. My own DM was institutionalised at one stage. We never talked about it and I would not want to speak of it at the time or now.
I think what is crucial to protect teachers is that they have enough (important) information about the students they teach so that they can make judgement class about teaching : this is a big problem in large school.
We also need to ensure students have rapid access to expert counselling... don't get me started on that one..
I teach a girl who attempted to take her own life very recently as I previously said, no one officially told me. The one big meltdown so far has centred around boys in the class talking - amongst themselves- what she called insensitively about mental health issues. A teacher can watch what they say and do but we cannot patrol everything that goes on. We aren't the thought police.
I think Plath is actually very popular with young people - precisely because she seems so damaged. Students like The Bell Jar too. I wouldn't want to have to hijack Plath though into a psychiatry lesson, so it can be an awkward choice for teaching. To be honest, the same issues of 'minefield' arise these days (I am trying not to sound reactionary) over any texts about/ featuring LGBT characters or issues (which are still few and far between, shockingly). But student and parental complaints / monas often come from different viewpoints there, so it's even harder to navigate!