My ex is "testing me" while we're on a break?

Yeah that craziness is called anxiety! The reason he says He is going to make up his mind whether to be with you or not. Is so you stick around. Its his way of keeping hooked like a fish. Are you a fish? Any person who puts another person through anxiety is sadistic (look it up) he is inflicting pain on you for his own pleasure. Do you really want to be with someone like that?
I mean your the smarter one here. You are the better person because you are looking to make things better. He's not worth it. I know I can't convince you, but ask yourself the following question:

"Does he really make me happy? Or am I just scared to try something new"

There is a lot of time and people out there.

Hey girl. It appears to me that the only thing being tested is how much control he has over you. Don't bite on this one. This is a good example of the games that people play in relationships. You don't need this.

Girl your being played around . A relationship is about giving and taking . He is not the only one in the relationship . You should tell him that you don't care what he says you don't want him back . Go and find another guy who will treat you like you should be treated . You deserve a lot better . Its not gonna be easy but it has to be done . Gd luck hun xx

Did he clarify why he wanted to go on a break?

It's a break, so you should go out with your girls and have some fun! Don't do anything you will regret, but just take some time for yourself.

But honestly, if he needs to take a break, then maybe you should move on. It's just natural to try to get rid of some of your feelings if he wants to go on a break. Doesn't he understand how much it hurt you? Why shouldn't you try to get over him when he wants to go on a break? I don't think you did anything wrong. I think you need to date someone more mature.

You should never have to change who you are for someone to like you or continue to like you. you don't need that in your life. there are so many other guys out there that would LOVE to be with you and that would treat you right. remember that a relationship has two parts to it, he can't have all the control. don't call him. no matter how much you want to be with him, if he doesn't want to be with you, it will never work. just be yourself. you are the one he fell in love with the first time.

Ok so why should you be tested, when he is the one that can't make his mind up. Sweetheart don't change just to keep him, and you shouldn't have to. It's like he is making you feel like you did something wrong, when why would you still totally love someone that doesn't know what they want. Prepare yourself for either way, but let him know that some things have to change on his part.