I'm so confused by my ex adhd boyfriend

Hi. 
Basically me and my ex boyfriend broke up multiple times because he has adhd and it is really hard for me to deal with. I constantly feel ignored, he bails on all my plans, he priorities everything over me, even a haircut when we havent seen each other in over 3 weeks. So I broke up with him so many times only to come running back because i love him so much. Finally i broke up with him but he sent me all these lovely messages that he always sends, then we agreed with a break. He told me to look after his heart while he looks after mine and that he would never get with anyone, its just purely to sort out his adhd. During this break he accused me of being on a dating app which is obviously not true at all and also he saw that i had been out and said that the pictures i put up on social media were disrespectful and im trying to get other guys attention and if im like that he doesnt want to be with me, this made me feel really bad about myself but the picture was not bad at all, i showed everyone else and they were like wth! Even my mum said theyre was nothinh wrong with the picture, nothing was showin but a tiny bit of leg, we sorted it out after i cried etc and carried on with the break. Then while this break had seen he had commented some really inopropriate comments on girls pictures and had been speaking to girls during our break to block me out?! But why would he need to block me out? We're on a break to get back together? . So I broke up for sure with him this time again, he sent me loads of lovely messages, saying his wrong he will change etc, his going to fight for me etc. So finally i said ill give you this chance to prove to me you will change and you love me, but i said dont talk to me, i want actions not words, as he always sends paragraphs of amazing words but does nothing. It was a couple days and i had seen nothing and i decided to send him a funny picture to lighten the mood and he ignored me for ages. I then saw more inopropriate messages on a girls pictures while he was ignoring me and he told me he had chilled with her the night before but they're just friends?! He told me he would beg for me back, come to my house and nothing. So finally now i have told him to never speak to me again, and gave him a massive peice of my mind. Again he played the sorry card and said he wont stop fighting for me. I ignored that but he hasnt done anything since but i have seen him putting pictures up of him having fun out and about while I'm sitting at home destroyed. I can't let go of him, i keep thinking he will come to me and prove himself but iknow he wont! HELP! Everytime ive caught him talking to girls he always has really good excuses and lies to me but never admits its bad until i get the long sorry message later. I suffer with ocd and anxiety myself and this relationhship has pushed me so far down that i was suicidal. I even brought the book to help him and me understand all the adhd behaviours etc an agreed to send him chapters every week. He has always told me ill always come running back and laughs. But this time i want it to be over. I want to stop making excuses for him and i want to move on but i physically can't . I can't imagine my life ever being happy again. I'm sorry this is so long.