i dont feel like i did much wrong

my boyfriend and i was dating for over a year.he cheated on me,stood me up on several important occations like b day,hid things from me saying i should trust him.i forgave him cause i really love him..recently he have been wanting to see my phone cause he seen me going through it.i didnt give it to him i told him he should trust me..we broke up i cried my eyes out nd tried to prove i wasnt.we went back out..we recently got into a big fight he took my phone nd look through it..now there are some things that would make someone think i cheated but really i have never..my bestfriend uses my phone nd text ppl from it because she doent have one.he also seen one from a guy that i was friends with nd flirted with me..he said thats why you didnt want me to see your phone.he was so mad told me he hate me nd to never tlk to him again.the next day he changed his number..he doesnt know them text wasnt from me now i look like a cheater.im so devasted cant get in contact at all..nd i know he will never tlk to me again.but he doesnt know the story..i feel like if onlyi didnt let my friend use my phone if only i didnt let the guy flirt with me..im more hurt cause although i dont feel like i did much wrong i took him back in eveything he did.nd he was so quick to leave me.what to do?