We all have done it, sitting someone down and playing them a record or a song that you absolutely love. The expectation is that the person you are showing it to will respond to it in the way that you have, especially if that person is someone you have feelings for. Unfortunately, more often than not they aren't as blown away are you are. It's okay, though.
Music can be very personal. Certain songs mean a lot to you because of where you may have been in life when you first heard it or what you were doing when it came on the radio. Over time these songs take on a life of their own to you they become more than just music. They become an expression of feelings, a theme song, a mood shifter, any number of things, really.
To expect someone to have those exact same thoughts when they hear it is unfair. Of course it bums you out when they are like "I mean, it's okay I guess" or "Nah, I don't really like it." That doesn't mean that their taste is bad or that you are incompatible. It just means that you have a strong personal connection to that music that everyone has to certain songs or records.
It is not always going to be like that scene is Garden State where Natalie Portman turns on The Shins for Zach Braff and he is just as blown away as she is.
Just remember, it's okay.