No way in hell am I letting someone like you fly by...?

Hi, im nicholas and im 18 years old. Recently I met someone over the internet (24) who i really hit it off with. We talked for hours and hours and he had explained to me that he had a difficult life because he had children, I was really supportive of this and made it clear that i thoroughly respected and understood his responsibilities and he was very responsive to this. After days of chatting we agreed to meet and were both really excited as we got on so well. I had finally felt like I found someone who was right for me. We met up and instantly i was struck by how attractive he was in person, which unfortunately made me act immaturely as a confidence mechanism and portrayed myself as a bit overly y. After a while he had said he thought i was really friendly, funny, smart and good looking however voicing the fact he wasn't sure if he wanted a relationship because I had such a youthful personality.He also said he was unsure because we were at such different places in out lives. This hit me hard and i immediately appologised and began to act like myself. There was no way I was letting someone that perfect get away. As I relaxed i found him easier to be with and we got on well. However because he is a person who lacks confidence I found it hard to strike some chemistry between us and get a spark alight. Eventually we cuddled and it seemed great, I really did like him so much. We kissed aswell and that was good too, if not a bit awkward. We left the bar we were in and went for a long walk and shared our feelings and had amazing discussions and it really did seem for both of us we had known each other for years. He would say things during the discussions now and again about being really unsure of what he wanted in life and in a relationship and said I wasn't his type but ured me he meant it in a positive way. After a short night of a few hours I half- heartedly went home and he kindly drove me. He kissed me goodnight and i felt the kiss was amazing. I was wracked with uncertainty however because I kind of got the feeling that he was a little disappionted.I got up in the morning and thanked him via text and he replied later that day with a text saying that he thought i was an amazing guy, really smart and funny and good looking, however he just didn't feel the 'spark of chemistry between us' and didn't feel like 'it was a relationship type thing' and knew in the long run it wouldn't work. I was astonished as to how someone could come to such a firm and somewhat harsh decision after meeting someone for such a short period of time. I lost some confidence, thinking it was to do with my image perhaps, but i called him and he was happy to explain that he just didnt feel the spark and thought it wouldn't work simply and he has a 'very clear vision of what he wants, although not entirely sure what that is'. He said he definately wants to keep in touch and hang out at some point because he felt ' we had such a close connection'. Im completely besotted and know if I had the chance i could perhaps change his mind because he just didnt know me for long enough. This has really been getting me down and I dont want to give up. What should i do to try and fix this and develop and interest in me. im so confused and truth be told it's really depressing me and frustrating me because he's just so stubborn and set in his ways due to having such a hard life. Please help with some advice. I'll award max points to best answer! :)