why hasn't my ex left my mind? I need HELP

It's like I'm helpless... what do I have to do to forget him?? It's been months now and nothing's working, tried being over worked and obsessed with my job, doesn't work, tried dating others but I don't want to use people and also no one else is fulfilling..I want to call him. I told him I loved him and blocked his number thinking that would help me stop. But I'm sitting here in love and don't know what else to do... I'm lost