Aside from the good surprise kinds of secret, secrets have no place in a marriage. If your bride knows you’re keeping secrets it’s hurting your marriage. If she suspects you are keeping secrets that is hurting your marriage too.
What qualifies as a secret? Pretty much anything you don’t share; even if it’s “no big deal”. In part, this is about communication and intimacy – she wants to know about you, about your world, about your thoughts, dreams, and fears. If you’re not sharing yourself in that way, it feels to her like you are keeping secrets.
Does that mean you have to share everything? Does it mean you need to give her every detail? Odds are she doesn’t care that much. Give her the highlights, then follow up if and where she shows interest.
Does not keeping secrets mean you should share things others tell you in confidence? That’s a decision you need to make for your marriage – and I’d suggest you discuss it with her. If your job puts you in contact with classified or private information, you will need to work within the bounds of the law and any confidentiality requirements. You also need to be honest with yourself about your bride’s ability to keep a confidence; if you share something with her, is there a chance it will go beyond her?
If you decide to share anything and everything, be sure to make that clear to those who might not expect it. Your friends need to know you are not going to keep their secrets from your bride. Personally, I think this is a good thing, and it can keep you from ending up in a bad spot.