The narrator espresses his despair with diametrically  opposed concepts. He is unable to rest, and yet he has no fight left in him.

By line 11 he  reveals a less paradoxical contrast: tratta he loves another therefore must not love himself. He revels in the joy of the sadness and discomfort of this love, and although the situation is almost like a living death, the cause of his pain his greatest pleasure.

Love is the subject of this sonnet, and is connected with the confusion, ambiguity and vacillation of feelings that are underlined in the sonnet. 

The poem is built From opposite sentiments and ideas  to reflect the full range of feeling that love can provoke.

While it seems that leads him to the brink of despair, the poet also seems intoxicated by it.

Line 11 is intresting as these two ideas are not usually mutually exclusive: it is possible to love another and oneself.

However, Wyatt is peraphs indicating that therelationship is one dictated by the Heart rather than the head; though the love feels right, the narrator cannot quiet his mind to the unsettling knoweledge that his love is not a pratical or logical codice. 

In the final rhyming couplet, the narrator makes it clear that he understands that wich causes him most peril.