Need some insight on my man, please!! 10 POINTS!!!?

[HI!]

I am in a long distance relationship with my guy for over two years. He is planning on moving in with me next year. We are both in our 30's, and because of our age, I cannot believe I am even going through with this.

We communicate frequently by phone, text, and email, but never through facebook. He is rarely on there because he thinks it is silly. Anywho, our profile pics are of each other, and has been that way for 2 years. Recently my sister came and visited me (whom I only get to see maybe once every couple of years due to location) Well, I changed my pro pic to my sister and I. And then I also posted a youtube video of one of my favorite songs (which happens to be a break-up song, but I love it) After that, I had noticed that my guy has been real short with me through texts....not his typical lovey-dovey self. Asked him what was up, and then he told me that it made him really sad to see that he is no longer in my pro pic, and is worried that I want nothing to do with him because of the song I posted??? We have a wonderful relationship. We never fight, we still act like we did when we first met each other. The sex is awesome....and he has been hinting at marriage, which I told him that I would be honored to take his last name when the time comes. So, why would he assume these things of me. Over a song and a pro pic? It is not like it was me and another guy, it was a silly pic of me and my sister. So, to prove to him that I do indeed love him, I dropped what I was doing in the middle of the night, and drove over 3 hours just to give him a hug and to tell him that I love him in person. He says he is sorry for all of this, but I have no ideas where this would come from. Could he be getting cold feet about moving in with me? Could he be having second thoughts? Opinions please!!!