How to get over a relationship which really never existed

I had a crush on someone for six months but never did anything about it because it seemed like it could never happen—it felt more like a fantasy. Then, he approached me, and everything felt dreamy. After a month, though, he started pulling away and didn't want anything serious. He took a step back whenever there was a conversation. I ended up becoming addicted to him, and he kept feeding into it by texting me occasionally. It felt like a limbo loop, and it eventually ended in disaster.