What should I do about him?

There is this guy I have been best friends with since 7th grade and we r in 10th now. I have liked him since the day we met...but he plays me. He will say he likes me when Im dating someone else then when I dump the guy he will make up an excuse. He has done this about 4 times now. Its really depressing because we are perfect for eachother. Well now he likes me again and I dont know if I should fall for it again...