I invited my ex-girlfriend to get married. I don't know whether she will come. If she comes, she can't let me go, can she? So should I get back together with her?

Of course we shouldn't get back together.

Now that you have decided to marry another woman, you should live with the woman who is going to marry wholeheartedly. Why do you want to have two feet on both sides

Give up what you have given up, take back your thoughts completely, and never expect to relive the old dreams, the second time.