Not sure what to do about this guy

I am a bit confused about this guy I've known for a few years. To begin with we lived together as flatmates for a year, I had the biggest crush on him that year and we were always a bit awkward around each other. He gave me the impression that he didn't like me in any way, friend or otherwise and was just a polite flatmate. But, when he moved out a year later, he was the one who kept in touch and occasionally visited. We talk more now than we did when we lived together.

Now he texts me occasionally, but is more interested in having a conversation when he's the one who initiates it. We've Skyped just once and it was for a long time. He lives in a remote place (we're in different cities) and has very few friends that he interacts with so at times I feel he's just charming and interested in me when he's bored and wants someone to talk to. Our conversations are lighthearted, sometimes bored, awkward and sometimes amusing.

A bit about him - he seems emotionally difficult to read and complicated and like he's always got a lot on his mind. My friends have found him a bit strange and a difficult personality. He seems shy and is really self conscious.It's been a couple years that I've known him now, but I can't seem to get over it or do anything about it because I'm just not sure what's going on and what I am to him. I've probably missed a few details trying to keep it short but let me know what you think as a 3rd person!