If it's ground water, the issue isn't water vapor, but rather just plain water. Is the water table close or higher than your basement slab? If so, not a whole lot you can do to completely stop moisture issues, as that basement was just built in a bad spot.
That said, the main solution would be a sump pump and drainage tile system. Any water coming up through the earth dumps into the drainage tile, into the pump well, and gets pumped out. Again, though, if the water table is already higher than the basement slab, that'll be a never ending battle as well.
That said, perhaps the issue isn't as much about ground water as you think. Does it get humid in your region? If so, then 'damp' basements are par for the course. Basement walls are usually always going to be cooler than the air, and, a such, will be were condensation forms in a humid environment.
To prevent that, you need to a) dehumidify and/or b) insulate the walls.
A dehumidifier constantly running tends to be a normal part of any basement in a humid zone, so that's a good start. Insulating with walls with XPS or EPS foam will help too, it'll keep the moist air further away from the cold wall.
I can't say if an air exchanger would help or not. If it's including an A/C system, it could help (as the A/C is a dehumidifier) but otherwise I have a hunch you'd just be pumping more humid air into the space.
Products like drylock don't do a whole lot. They're not strong enough to prevent hydrostatic water pressure (high water table) and do nothing to prevent condensation. They're a bit of a gimmick.
I think based on the comments I better understand your scenario now.
Building Science has a lot of great information on basement insulation and the suggested method is to use XPS foam against the walls, optionally bats between the studs and no vapor barrier (since the XPS foam is the vapor barrier).
I would suggest that you use 1 1/2 - 2" XPS foam against the walls, and then space your studs another inch or so away from the wall (to allow your water to drain). If you need higher R values then the XPS provides you can use bats between the studs and I would suggest something like Roxul insulation which is stone wool instead of fiberglass since it is not affected by moisture like fiberglass is.
It would also be advisable to use steel studs so that they don't rot should they come in contact with moisture. You might also opt to put the bottom plate on top of a piece of XPS foam so that there is a less likelihood of the metal studs rusting.
Best Answer
Providing proper drainage outside combined with sealing is my preferred method. I have had walls that may have been close to what you have I dug down installed drains and backfilled with rock (no dirt) that home went from rivers on the floors to dry walls. If possible to divert the water before it enters it takes less energy to have a comfortable basement in the winter (sump not having to pump all the water out of the house that came in to me that made sense it worked quite well so over thinking it? No I don’t think so but this could be viewed as an opinion question.