Confused - can't get him out of my head

I'm 17 and had previously had no romantic experiences whatsoever before the following event.

Basically, I was on a bus home from school and a boy turned round to me, said hi, and we started chatting. He gave me his number and we texted lots - he was always extremely flirty over text, always telling me he thought I was beautiful and lovely etc. And I couldn't believe my luck. I couldn't believe that someone was potentially interested in me, but I didn't complain, because I liked him a lot. We used to get the bus together a lot and although I'm extremely shy, I felt very comfortable around him and we had lots of nice conversations. He was never usually flirty in person, that was always saved for texts. He even told me he loved me over text once, after knowing him about a month, and although this caught me off guard, I didn't think much of it - I just thought that there was a mutual understanding that we both liked each other. So anyway, he asked if I wanted to meet up with him one weekend, and we went to the park together. He was being really flirty with me, and acting like we were together. We were sat together chatting for ages, and he had his arm round me and was holding my hand, and he kissed me a couple of times. He texted me that evening saying he'd had a nice time. I was over the moon, because by this point, I liked him an awful lot, and thought it was apparent that he liked me too. Everything was going great.

Then, he texted me the next day saying that he thought I was a lovely person and he had a nice time with me, but that it was a bit weird because we were mates, so he'd rather that we were just friends. I couldn't quite believe it. I was really upset, and asked him what he was playing at. He said that he knew he'd been an idiot with me, was sorry for leading me on etc. But still wanted to be friends. I still couldn't work out WHY he led me on in the first place - he initiated everything, it wasn't just me getting carried away with my emotions. I asked him why, he said he didn't know, he might have liked me, but he wasn't sure, and he didn't know why he kissed me. I was annoyed at him for the longest time. It was the summer holidays, so I didn't see him for a couple of months. I still wanted to be friends with him, but I was sure that I was over him.

Then we started back at school, and I started seeing him on the bus again. Things weren't awkward between us, and I was reminded of why I liked him in the first place - I enjoy his company immensely. Anytime I'm with him, I just can't help but fall for him again, and it's bringing me down. And now, I just CAN'T stop thinking about him, it's getting a bit ridiculous. I still have feelings for him, and there's still a bit of hope in me that he'll have feelings for me too, even though I know that will never happen and he only sees me as a friend. I know I'm being stupid, so why can't I just get over him?

I suppose I'm writing this because I still can't work out exactly why he would lead me on, when he seemed so lovely. Was he just being stupid and wasn't sure what he wanted? And also, I'm getting pretty annoyed with myself because I just can't stop thinking about him, and I still have feelings for him, even though it's all futile because he evidently doesn't like me. Any feedback would be appreciated, since I'm greatly inexperienced in all of this.

Thanks.