Is it possible for my husband to receive message on his phone that have been sent to me. Is it possible for my ex husband to receive my message on his phone. Because I don't understand how he is finding out things he shouldn't know and relieving pictures sent to me that I have not sent to him. How do u stop this from happening.
Do you share an AppleID? More generally, does he know the password to your AppleID. If so, then yes, he can tell Apple that his phone (or Mac) is one of the places you want your messages to be delivered.

If that's not what you want, change your password.