Atwood, Margaret."You fit into me"

This poem is about love. The author loves someone so the author cannot stop looking at lover.
The author always looking for lover and keeping on eye on lover, so the author said "You fit into me like a hook in to an eye". The author cannot stop following lover with his/her own eye. "a fish hook an open eye" means that the lover is like a fish hook so the lover always make author to follow his/her move. And the author's eye is always opened to see his/her lover every second.