A charge frequently leveled at the Catholic Church is that Catholic worship the Blessed Virgin Mary, which would make the guilty of idolatry. The answer of Catholic theology it that this charge is untrue. The devotion given to the Father, Son, and Holy Spirit is designated by the Latin term latria. The high veneration given to the Virgin is called hyperdoulia, and the veneration given to saints is called doulia.
Protestants sometimes don't find this response satisfactory, because they think that the actual practice of Catholics in the devotion to the Blessed Virgin turns the distinction between hyperdoulia and latria into a distinction without a differences. Pilgrims to Our Lady of Lourdes will walk for miles on their knees, an act of dedication that few perform in devotion to the Godhead.
Nevertheless, the answer of Catholic theology is quite clear: Catholics do not worship Mary.