how to get over my ex .. please help...

my ex and i broke up a year ago and this weekend we spent time together and he admitted to lying to me about not loving me anymore and apologized for pushing me away. but after the first night he decided he just wanted to be friends. i asked him when he stopped caring and he said 6 months after we broke up. and he didn’t tell me any of this before because he said i lied to him and he thinks something happened between me and a friend of mine. because when we were together we had just broken up a couple months beforehand and i was feeling sad because i found out he talked sexually over text to girls when we split for a month and i had my friend come over one night and i cried and talked about my ex all night. and anyways. my ex called the next day and asked what i did that day and i just didn’t mention it but he says i lied saying he asked if someone came over and i said no but that’s not what he asked but anyways. he basically thinks i cheated and lied and he also said we argued a lot. i’m heart broken that he assumed i would do something so awful. i would never ever think of cheating on the person i love. and i tried to tell him nothing had happened and i told him what did happen , that i was crying and he looked cold and like he didn’t believe anything that came out of my mouth and i was going to cry. it broke my heart to be perceived that way especially by someone i loved. and i missed him and i wanted to be with him. and everything is messed up because he thinks i did something. and i don’t know how to accept that. i need advice and help.. i want to be with him

but that can’t happen ...and i can’t seem to get over him ... and i know i have to. but i don’t know how to.