Banks have internal policies about what and with whom they will share information and they send a copy of that policy to their clients regularly. This is required by the the Gramm-Leach-Bliley Act. In general, sharing a credit history with a different "consumer" than the one who provided it would be a violation of the GLB. I would not expect them to do so.
Normally, I would not expect the bank to even show you your own credit report. When a bank requests a credit report, they use that information purely internally, they do not provide credit reports to other people, not only for privacy reasons, but usually the contract they have with the credit bureau requires them never to share credit reports with other people.
Any information on the loan application itself will be visible to all parties to the loans.
(By the way, credit reports are not secret information. It is very easy for a person to obtain a credit report for anyone. This can be done by various methods. Most private investigators will provide you with anyone's credit report for a small fee, perhaps $100 to $200. So, if your wife wants to see your credit report, she will have no problem doing it.)