This is why you see the frost.
Nails in my attic are dripping wet.
A point often overlooked is that since it s winter the water freezes on the cold nails.
Every nail chisel tip in the attic is dripping.
In your case a attic access hatch or doorway is leaking badly allowing quantities of water laden air to come in contact with your roofing nails.
If you have a friend in the attic ask him to direct you to a sturdy spot where the nail can bite into the wood.
Could the roof have cooked itself in 8 years like that.
The nail chisel tips are rusted.
The nails that you see in your attic get as cold as the outdoor temperature.
The air in the attic has water in it and it condenses on the cold metal.
If the women don t find you handsome they should at least find you handy.
These same condensation points the roofing nails will often map exactly the drip stains found on the attic insulation or attic floor below each nail.
I have a roof that is 10 years old gaf timberline 25.
Also my wife had the roof done before we married.
Not sure if that has anything to do with it.
Not sure there is much you can do about it other than maybe spray the tips of the nails with some rubber coating to insulate it from direct cold wet air contact.
Hammer a new nail into the roof about 1 inch above the hole from the previous nail.
If the problem is the result of water or moisture penetrating the foundation or floor slab there are many remedial actions which may help.
Excessive attic moisture condenses on the cool metal surface of the roofing nails causing corrosion or rust on the nails and stains on the surrounding wood materials.
The best solution for controlling moisture is at its source.
All of this is one half of your problem.