Do I give up ? or what do I do ?

My Ex is my first love , i really love him but its been almost a year with him in my life anymore . every time i try to move on it doesn't work out because i still love him . Me & him did everything together , late night conversations , morning thought night talking , telling each other everything . I lost him , took him for granted now i don't know what to do , i love him more then before he always on my mind i tried to move on but i can't , i wanna tell him how i feel but he has a girlfriend now & he loves her a lot & i want him back but i don't know what to do .