IM DESPERATE NEED OF GIRL ADVICE

So I am 18 and my boyfriend is 17. We were together for almost 2 years and we finally called it quits because we were having too many issues, with trust and always fighting. But we have still been trying to work through somethings before we tried being together again. Since we officially ended things, he's been with 2 other girls. One he started being a thing with while we were still together but claimed they were just friends. And the other is a girl who he knew I have hated my whole life. I really love him, but I am so angry with him because I feel like he is focusing on everything except fixing our relationship. He claims to still love me and still want us to work, but his actions don't show it. I don't know what to do. I don't want to be mad at him, but I am so frustrated because I feel like I have been trying so hard and that he hasn't been trying at all. I have been putting all I have into fixing things with us for about 2 months and hardly nothing has gotten better. I don't know whether to stop trying or to keep trying. I love him and the thought of life without him scares me and makes me upset. But I am really hurting right now because I feel like he honestly doesn't care, but I love him more than anything.

Does anybody have any advice on what to do?