OK, I know this is probably a really hard time for you but I just want to let you know that even if your situation seems almost impossible, you can still get your ex wife back if you follow these guidelines.
First, do not call her or communicate with her at all in the beginning...
You have to let her sit and think about everything that just happened, you have to give her time to herself.
You have to keep the push pull theory in your mind when you're dealing with something like this.
The push pull theory is when you try to pull someone in too much they'll just push you farther away but when you push someone away they'll want to pull you back in because of fear of loss...
People want what they can't have and that's what we're trying to make happen here.
You have to display high value for this to work so first and foremost you have to find out what it is that cost your marriage to collapse and fix that issue right away.
The problems could stem from things like jealousy, cheating, insecurity, boring sex, etc...
Your have to put your finger on exactly what the main issue was and take the proper steps to go about fixing it or else there will be no point in trying to put the relationship back together again.
The next thing you're going to need to do is take on a much more positive and confident attitude.
If your ex wife calls you, do not say anything about the relationship; make small talk like you're talking to an old friend.
You want to show that you are fun, independent, and have high value as a man meaning you will be happy and positive no matter what happens to you or the relationship.
When you do this it will become much easier to get your ex wife back.