How do I get over him?

I am infatuated with this guy, but one day he's close and sweet, the next he's distant and cold. My friends constantly tell me he likes me a lot, and his friends tell me to be patient and give him time. So I just decided to give up... He's not worth my time if he's going to be hot and cold. So how do I get over him? :( I've been trying, but it's not working!