context: elizabeth's brother drowned at a young age, making her father very over-protective of her. she eloped against his wishes with the poet, Robert Browning, showing how important love was to her
structure: repetition of "i love thee" sounds similar to a prayer so she could be praying that someday they'll be able to be together one day. At the beginning of the poem she makes references to her love being limitless
"how do i love thee?" - questions how she can prove/express how much she loves Robert Browning
"i shall but love thee better after death" - could suggest she loves everything about Robert Browning, with every emotion. even with every 'breath' she takes she thinks about him