I know what you feel when you think he isn't listening. It's like you just want to shake him and unscrew the top of his head so you can look inside to figure out exactly what he's thinking. Even when you tell him that he's not listening, that's not what bothers you so much, it's that you don't think he feels it.
And you want to make sure that
he feels it, as much as you do. So you talk more and more and maybe even get more animated. The intensity starts to build and your feelings bubble over in an attempt to wake him up emotionally. I get it, but you're doing it all wrong. He doesn't like that drama like you do, in fact it overwhelms him. He's not a girl and before you roll your eyes at me hear me out.
What he craves is serenity. He wants an emotional connection with you...without having to go through an emotional workout. He isn't your girlfriend which means, sometimes he'll "get it" right away, and other times...not so much. Don't get frustrated because he can't read your mind in a way that your sister can.
Even though he's quiet I promise you he's listening, he just has to sort through all you're telling him. If you want to know what's he really thinking, I can help you with that, :-).