Poetry Help! "Indeed, indeed, I cannot tell"?

[Daniel]

Indeed indeed, I cannot tell,
Though I ponder on it well,
Which were easier to state,
All my love or all my hate.
Surely, surely, thou wilt trust me
When I say thou dost disgust me.
O, I hate thee with a hate
That would fain annihilate;
Yet sometimes against my will,
My dear friend, I love thee still.
It were treason to our love,
And a sin to God above,
One iota to abate
Of a pure impartial hate.

Henry David Thoreau

The main question I have is how does the DICTION of the poem contribute to the TONE of the poem. And how does the TONE of the poem contribute to the THEME of the poem.

So what words would you use to describe the diction and tone?

And what is the overall theme, what is Thoreau trying to tell us?

Thanks in advance! This is a really nice poem.