There is something missing here, I am guessing you have been driving your wife's car for more than three years. If you have, you have lost the claims you had on your old policy. Alternatively, you might be saying you have not accrued any no claims discount of your wife's policy, which is correct, as you would not.
If you have been driving your wife's vehicle for less than three years, then the no claims bonus you will have had from your own insurance policy will still be valid.