How can I take my sonnets to the next level?

Sonnets require extreme precision. You've got the basic idea, but your rhymes are not very well thought out and your scansion is weak. The first, fourth, and final line are the only ones in good iambic pentameter, and if you're not going to use I/P in a sonnet you might as well be writing free verse. Also, note that in a sonnet the focus falls on the closing couplet. It should "inform" the rest of the poem rather than simply re-stating a theme. A good sonnet reads like a riddle. Also, the closing couplet ABSOLUTELY has to rhyme. "Other" and "lover" don't. Keep at it.