Yes, Only if she is not deleting the incoming and outgoing texts and she has the right name in the contacts that goes to the appropriate text. For example if she has the name Sharon in her contacts for 555-5555 and there is a text for Sharon in her message box BUT the number really belongs to Frank. Well it is impossible to know for sure. Unless you call the number and the person is willing to tell you who they are. Been there done that and it sure stinks. Good luck dude.
Sure shes your wife so you have the Right to do it to her and she can do that as well just check it ..
There is a wedge in the relationship, who put it there? Remove it.