I dont know if im in love, or if i am going mad.?

I really need some advice on this. I am a 14 year old boy. and to be in a situation such as this, seems insane to me. ok.. ill start at the beginning. I took part in a theatre performance thing in plymouth with around 20 other young people. I didn't know anyone before i went, and i didn't know what to expect. I went and within the first few days i was getting on very well with everyone, but there was a girl that i especially "clicked" with. after a week or so, we became more than just friends, and started going out. I though this was just like one of those holiday flings i had encountered before, but i knew something was different when our relationship became somewhat ual. The week we were together was one of the best weeks of my life, and she was one of the main reasons. When we had to leave plymouth to go back to our homes, it was very emotional. but this kind of thing usually happened when 20 or so people spend 2 weeks living together. I really missed her during the first few weeks. i could hardly think of anything/anyone else. A month or so later i was asked out by another girl, and i accepted. but i still felt really strongly about the girl i met in Plymouth, so it didn't work out. About 4 months later i felt like the feelings i had for her were decreasing, which was a relief. As i wanted to stop thinking about her constantly. I got an email from the theatre company proposing a reunion in london, which took place yesterday. I wasnt really worried/excited about it as i had got over the experience a month or so before. I arrived... and saw her again. We hit it off again, and got on like we had never split. Once again, it was time to leave... and it got emotional again, noone else seemed to be affected by the fact that everyone was leaving again, apart from me and her. I never ever thought she liked me as much is i liked her... but she made it clear how much she actually missed me yesterday. I now feel like i did when we first split up. I cant stop thinking about her, but i know it is not possible for us to be together as there is a VERY large distance between us. around 100 miles or so, and i dont know what to do. I am so confused at this, as i have never encountered anything like this before. :(.