Why do I miss him?

I have had this crush on this boy for a long time! We went out…broke up…dated..off and on for over a year! We both had sex. Lost it to each other! I fell in love with this boy! Its hard to beleive after everything that has happened with us! So he is a year older then me. He left and went to college in nebraska, and im stuck in our home town with another year of high school. Before he left I told him we need to see each other. He came by we talked hung out…I said bye…he left, I cried for hours! It was so hard for me! I didnt know what to do. I talked to my girlfriends but it doesnt help my situation. So I was like he is gone, we wont talk, well both move on. so and so. anyway…he started to text me, and talking to me. I was suprised at first but I didnt know how to react. so I been talking to him. I didnt tell him this before he left, I wanted to tell him I loved him! So I did! The day after he left when he texted me I told him! He didnt know what to say. I for sure thought I pushed him away by telling him this. The thing is…I told him, and after he was glad I told him, and now he talks to me like every day!!! Its weird…the other day he had the guts to say do you miss me? I said of course you nerd…he said he misses me too! UGH why did he have to say that! I don’t know what he is thinking!?!? or doing?!?! Im so confused! But I miss him!! I don’t know what to do?!?! someone help?!?!