When I feel love and attraction for someone, it is in part because I sense (and the love itself engenders a sense) that I can share true emotions. Even when those emotions are difficult, I feel free to share because my love tells me it is safe to bare all.
When "all" includes the love itself for that person, I share it.
However, when the recipient does not feel the same love--a love to receive anything--the person might still kindly assent to listening like any good friend would do. But, not possessing a reciprocating love--a true desire to share all emotion--the person may listen while becoming uncomfortable in hearing what is difficult to hear.
I share because of a love he does not feel. Not feeling it, he listens out of duty of friendship, but lacks the capacity, the love, to truly bear it. Our time together becomes strained, restrained, and while wanting to be available, he does not know how and time spent together diminishes, first in quality, then in quantity.