Was this my fault for losing this guy? Or was he just a jerk?

I went out with this guy and was totally into him. I ended up sleeping with him the second time around, he told me all these sweet things that I was beautiful and that I could even visit him when he went overseas. Anyway, he went overseas and was planning on being there for awhile, we kept in touch on facebook, I wrote him sweet things and he wrote me back. When I didn't hear from him, I would keep writing to him -just sweet messages. He told me to leave him alone and accused me of being "obsessed" with him. WTF? He was the one that found ME first. I found out that he got engaged. I was hurt and pissed. He told me "We never discussed a relationship or anything close to that." Ok, we didn't talk about a relationship, but seriously, he told me things like, "You could visit me overseas," and "I miss you too, wish there was something we could do." Doesn't that make you think there's something more? Was this my fault for not asking him for a relationship? I wanted things to just happen. I was waiting for him to ask me that he wanted something serious or that he wanted me to be his girl. I keep beating myself up over this!!! What went wrong?