@jonnythan Said
If she tells her friends, she'll never be able to comfortably hang out with them with her husband, ever again. It will become public knowledge among their entire circle of friends and possibly coworkers.
Imagine taking your husband to your friend's wedding, and everyone there knows what he did. It will not only be very uncomfortable for the OP's husband, it will be very uncomfortable for the OP.
She will have to live with the public shame of "having the husband who took the creepy pictures" just as much as her husband will.
If she leaves him, then by all means tell everyone. But if she can work it out with him and move on in their relationship, it will be far better for both of them if it's not public knowledge.
To add to this for the folks that don't seem to understand, the OP is not letting her husband off the hook by not telling her friends. She is solving a marital issue and coming to a sound and rational solution. You can't run out and tell your friends that your husband is taking secret photos of them because it's going to cause even MORE problems for everyone involved. Yes, marital issues are difficult to deal with, but you do not need a support group of friends to get through them. The OP should first sit down and calmly talk to her husband and find out what's going on. Then give him the ultimatum of trial separation or counseling, or tell him to pack his bags if that's what she wants to do.
Getting her friends together to gang up on her husband when she hasn't even made a decision to stay with him or divorce him is the worst possible thing to do. If she does reconcile, her friends will all hate her husband, not to mention what her friends or friend's spouses might do or try to do to get back at him. Telling the friends is a step that comes later on down the line, well AFTER the husband and wife come to their own decision on what to do.