Trying to Fix Things With Him

My ex broke up with me about a month ago. From what everyone's been telling me and messages I've read, he believes he's been treating me like shit and that he's been causing me too much anxiety and stress. It's not true at all. I tried telling him that back when this started but it was all over text since I was away and he doesn't believe me. Our friends have been telling me that I should talk to him (apparently he misses me and he's not happy), but I'm scared. There's so much opportunity for things to go wrong I'm terrified. My parents told me I should leave him alone, I don't know what to do. I miss him so much I can't breathe sometimes, help