Is it normal that i can't forget this guy?

There's someone that pops up in my head 24/7. Everything I do, reminds me of him.
We first met at Disneyland. I went with a few siblings and my two elder cousins. He got ditched by a couple he went with and we ran into him twice. Because of the fact that he's my cousin's cousin, he decided to tag along the second time. After hours passed, the park was so we decided to go out and eat. I had some pretty hilarious, laughable moments but for once, someone, that guy, didn't laugh his butt off at me.
Since my cousins were still in town, we met up with him a couple more times. I started texting him the following day of our meeting and we exchanged thousands of messages for about 3 months, not missing a day. Although my feelings did get through to him, and it was obvious that he too had feelings for me, we both knew we could never be together. "Age is but a number," even if you believe that, society doesn't. Our ages were really far apart... not just by five years but fifteen years apart. In all reality, older men didn't interest me but for some reason, almost everything about him did (He's no pedo either).
Our relationship, all was going well but things took a turn for the worse. When he falls for people, he falls for them hard— gets up quickly, not allowing that person to help him up.
One day.. he changed. He stopped talking to me as much and talks as though he really has no interest anymore.
I know he's doing this for both him and myself so I too try my best to avoid conversing. I love and miss him so much... even if I remind myself of all those bad qualities he has, I still can't forget. I do things differently, I've looked for someone new, am doing something 24/7, yet my results don't seem to differ.
It's been 2 months already... is this normal..?