You are always a Catholic, once a person is baptized, that mark of the Holy Spirit is on your soul. You will always be a Catholic, whether an active one or a lapsed one, is up to you. And you will eventually (at the moment of your death) tell Jesus why you denied your Baptism.
And, by the way, I have never denied my Baptism. If the Catholic Church believes I did such, that's another one of their silly rules without basis in anything but ancient tradition. All churches recognize baptism from any other church, FYI.
Actually, not only I did not deny my baptism but was baptized again. Only this time it wasn't something done to me at somebody else's request, but something that I chose to do, to follow my Lord and Savior. Obviously we disagree on infant baptism, but can you deny the validity of a baptism chosen as an adult?