That is going to be a constant maintenance issue. The bricks will always absorb water, and need to move. The grout does not always move as the bricks do, so you get cracks.
You could repair it, and then seal it. Your location is also frost damage prone.
Unless someone has seen something for the northern climates, sealing it and hope for the best is all I have as a solution.
Good luck and tell us how it works out...