Your ex is not kidding around, they are ignoring you, and being extremely cold for a reason! You see, your ex is fed up, and as long as your ex feels this way, you are at a huge risk.
You cannot get your ex back, unless you take some serious measures, otherwise your ex will just move on and find someone else! Here is what you must do to get your ex to like you again...
Drop the ego and admit your mistakes - Whether you do this through a simply apology, or you decide to tell your ex that you were wrong here or there, either way, you need to drop the ego.
Sometimes an apology is all it takes, and it doesn't hurt to say you are sorry.
Owning up to your mistakes is a huge step in getting your ex to like you again, because it starts you on a psychological path with your ex, where he/she feels you are understanding and agreeing with them, and ultimately with what he/she wants.
Keep your looks up to par - When we get comfortable around someone, we start letting ourselves go.
We think they should accept us as we are over a certain period of time, and suddenly our body, clothing styles, and other things are not too appealing.
At least make sure that you are trying as hard as you can to look your best, if you even expect your ex to take you back.
You see, people do get bored with looks, especially when they see the same thing daily, which is why you need to change a few things up so that your ex can be interested in you again.
Quit acting like a baby - Games are for kids, and so is acting like a kid! If you have insecurities get over them, if you are really desperate, then find a way to love yourself.
Either way, you need to stop demanding things from your ex as if you were a kid, and you also need to stop acting like a baby when you don't always get you way.
Relationships take two people, not just one, and always freaking out when things aren't going as you want just seems really childish, so grow up.