I assume you want to know if you should do something about this. It depends on what the attorney told the other. Some things they have to tell the other side, it is called discovery. Other things they are not allowed to share.
If there is reason for you to believe that your attorney relayed confidential information to the other side that this side had no right to possess, you can file a complaint with the State Bar against the attorney. If you feel that it compromised the divorce proceedings to your detriment, you might then be able to file a malpractice suit.
But these are serious allegations, so first I would try to find out what exactly was exchanged between the attorneys and why.
