You have fulfilled your duty as that of his boyfriend by begging him to get help. You can move on now. Advising the guidance counselor is a great idea.

You have gone what you could!

From an old song by Alice Cooper:

I don't want to see you go,
I don't even want to be there.
I will cover up my eyes
And pray it goes away.
You've only lived a minute of your life
I must be dreaming,
Please stop screaming.
I don't like to hear you cry.
You just don't know
How deep that cuts me.
So I will cover up my eyes
And it will go away.
You've only lived a minute of your life
I must be dreaming,
Please stop screaming.
Steven
I hear my name. (Steven)
Is someone calling me ?
I hear my name. (Steven)
That icy breath,
It whispers screams of pain.
I don't want to feel you die,
But if that's the way
That God has planned you,
I'll put pennies on your eyes
And it will go away, see ?
You've only lived a minute of your life
I must be dreaming,
Please stop screaming.
(Steven) (Is someone calling me ? - No)
(Steven)
(I think I hear a voice,
It's outside the door.)
(Steven) I hear my name.
(Steven) (Is someone calling me ?
I hear my name.)
(Steven) (What do you want ?)
(Steven) (What do you want ?)
(What do you want ?) (Steven)
(I hear my name.)

I am not saying that he would die. Just that you have done what you could.