how I supposed to do?

something missing from my life.....I missing someone who I really love....he leave me because of other girl....I SUFFER until now because I hope he can come back to me,but he didn't come.....I wonder,what have I done???why he leave me???I doing everything for him but he treat me like this....until now I still waiting for him....I hope one day he come to me because I really miss him.....3years with him...I cannot forget wahatever I done with him...everything still in my memory...hope Allah always bless him and may Allah bless our relationship....