When a relationship breaks down, it is hard for both parties involved. You are probably thinking that you are the only one that is hurt, but that simply isn't true. You obviously had a special bond between you and nothing will ever change that. The thing that will change though is that they will be in someone else's arms within a matter of months if you don't get up and do something about it. If you leave it to fete, then the chances are that nothing will ever happen, so take matters into your own hands, don't just hope things pan out.
You know you love them, and you know that part of the relationship was habit. Analyze what went wrong and what you can do to change it for the future, other you will never be able to get them back. I know it is a hard time, but just keep in the back of your mind that you will be alone for good if you don't fight one last time now. Relationships disintegrate for a number of reasons, but most people just give up and regret doing so for years to come.
My advice to you would be to get some professional advice. I'm not talking about articles that can be found scattered all over the internet, full of useless information! I'm talking about seeking advice from a professional who has experience in the field and has proven methods that will show you how to win your ex back for good!