Did you ask your T why she thought it was good?

I don't see how your analogy to beating a child for being hungry is the same thing.

It seems like you are putting great importance on your interpretation of your T's response, without considering the possibility that investing thoughts of harm with the kind of energy that comes from focusing on them is actually a negative rather than positive thing.

I have found it really useful when my T encourages me to think of thoughts as "just thoughts." To not be afraid of them, to not give them huge significance, to accept that human beings have the kind of "monkey mind" that makes all kinds of thoughts rolling through the head as normal and expected. For me, being able to just let those thoughts go because I am comfortable with them is one of the most useful skills I have developed. And if you've ever tried meditation, you learn that being able to let thoughts go without ruminating or dwelling on them or getting freaked out by them is a really good thing.

I would question whether it's really necessary to dig into thoughts of self harm, explore where they come from (although who knows, probably). There is definitely a school of thought among T's that focusing on self harming thoughts (plan and action are in a different category) encourages more self harm in the short or long run.

So I would also question whether it's terribly tragic for a client to "keep" thoughts of this nature to themselves rather than make them a subject of therapy. It sounds like distorted thinking to me.

But it also doesn't sound like you've really talked about *this* topic with your T. As in, you don't seem to understand why she'd say "good", so maybe you should ask her about it, and be open to interpreting what's going on in a less destructive way.