Assuming that the two of you were baptized using the Trinitarian formula, your baptism is viewed by the Catholic Church as sacramental, and confers the exact same salvation. It was decided in the early Church that even laypeople could validly baptize if they had the correct form, matter, and intent.
The reason why the lapsed Catholic can return to the Church simply through a single confession is that it is assumed that the lapsed Catholic has been properly educated by the Church. Even so, it isn't uncommon for the revert Catholic to come back to the Church via RCIA or further catechesis by a priest. An example that I know of is one of the professors at my college who returned to the Church and went through RCIA with his wife, who was raised Protestant.
As a side note, it's only Protestants who view priestly baptism as "erroneous"... remember that the Catholics and Orthodox here likewise view your lack of ministerial priesthood as "erroneous." And the first group of Protestants were lapsed Catholics.
And the first group of Protestants were lapsed Catholics.
Well, Calvin would be included in that "first group of Protestants" and he certainly objected to Rome's understanding of Baptism.
Here's a good comparison of the different views of baptism...