Answer:
The theme of "Heart to Heart" is the inability to control one's desires, being unable to explain or know how you feel, and struggling with the emotions you have.
Explanation:
The theme can be supported by the words "I want, I want — but I can't open it: there's no key." this sentence from the poem supports the idea of an indecisive struggle with emotions and desires. In addition, the section "I can't wear it on my sleeve, or tell you from the bottom of it how I feel." emphasizes the lack of emotional intelligence. The heart is continuously referenced as nothing more than an object, taking a logical approach that implies rejecting one's emotions before switching to a metaphorical perspective that feels more willing to accept those feelings.