Sorry, but you need to go see a lawyer, pronto.
When woman says she wants some time to see if things will "work out", she really means that she's already done, but doesn't want to tell you just yet.
Hire a lawyer, and get mean if you have to. It will be best for you and your children.
In the meantime, get some counseling or talk your feelings out with a good friend. Take care of your grief that way, don't let the wife use it against you.
And believe me, she will.....simply because you don't believe that she will.