I missed my chance what do i do?

Anti CookieCutter Asked: I missed my chance what do i do?

So i met this guy like a year and a half ago, me and him instantly clicked. Suddenly i always wanted to be with him. I constantly was hoping he liked me back. We became best friends for awhile. At this point i was sure he liked me too, but i was too shy to anything. He would call me and want to make plans (specifically when his parents werent home) I always caught him looking at me and he would he was always the first one there for me when i was upset. Then one day his older sister told me that yes, he did like me too, BUT he has a girlfriend back in his home town. I felt both happy and heartbroken at the same time. I started to drift away from him, and he just stopped talking to me.
And slowly he became that person that i "say hi to in the hallways from time to time". I tried to tell myself "you'll find someone else". And i did….kinda, i never really "clicked" with any of the other guys, one of them actually hit me a lot. I distracted myself with schoolwork, but everyday, for 10 months, he was always in the back of my mind. Around March, i saw him and i just couldnt take it, i had to talk to him. I walked over to him and just said hey. We started catching up, i found out he broke up with his old gf, but now he has a new one. Again, i was heartbroken. I felt like before we drifted apart, i atleast had a chance if i just waited. And now i missed it. Now its summertime and i dont have schoolwork to distract me, so he's on my mind all the time. I feel like ive lost not only someone i love, but also probably the best friend i ever had. Im making plans to see him to reconnect and try to have our old friendship back. Im making plans to see him this next week to hang out, how should i act when i see him and what should i do?