First, if your girlfriend has a priest she is close to, he would bethe best person to talk to about this. He might be okay officiatingthe ceremony even if you are not Catholic.Unfortunately, there is no "quick" way to convert to Catholicism. Thechurch takes its membership fairly seriously and asks that adultswishing to become Catholic go through the Rite of Christian Initiationfor Adults (RCIA) (described below). Another option--there might bethe chance that you could find a Protestant minister to co-officiatethe wedding or even a Catholic priest who will celebrate the servicewithout requiring you to be Catholic.(information below taken from (http://www.catholic.com/thisrock/1995/9504qq.asp)Another way--you could become baptized (again) in the Catholic church,which would essentially initaite you into the church. From there,since you have received your basic initiation by virtue of yourCatholic baptism, what you need now is to learn the Church's teachings(which you are already doing) and make your first confession and firstCommunion and to be confirmed.Under canon law, you as an adult do not need to undergo formalinstruction in order to make your first confession or first Communion;informal instruction is sufficient. In fact, &quotSacred ministers maynot deny the sacraments to whose who opportunely ask for them, areproperly disposed, and are not prohibited by law from receiving them"(CIC 843).You must know, understand, and accept the Church's teachingsconcerning confession and the Holy Eucharist. The person who teachesthese to you does not need to be a priest or catechist, just someonewho knows and will give you the straight story concerning the Church'steachings on these sacraments as found, for example, in the Catechismof the Catholic Church (see numbers 1322-1498 in the Catechism, about40 pages of material to study).Once you understand and accept these teachings, you can go toconfession--anonymously if you wish--and explain to the priest thatyou were raised outside the Church and that this is your firstconfession. You will need to confess all the post-baptismal mortalsins that you can remember, indicating to the degree possible thenumber of times or the frequency with which these were committed. Thisneeds to be done before going to first Communion.Because you will have learned and accepted the Church's teachingconcerning the Eucharist, you can begin going to Communion like anyother Catholic. No special permission is necessary. &quotAny baptizedperson who is not forbidden by law may and must be admitted to HolyCommunion" (CIC 912). Basically, those forbidden by law are childrenwho are too young, uninstructed, or improperly disposed (CIC 913-4),people under a penalty of excommunication or interdict (CIC 915),those who have committed a mortal sin since their last confession (CIC916), those who have already received the Eucharist that day (unlessthey take an active part in a second Mass or if special circumstancesapply ), and those who have not fasted for an hourbefore going to Communion (CIC 919).To receive confirmation, which you should do as soon as possible (CIC890-1), you will need more instruction: &quotApart from the danger ofdeath, to receive confirmation lawfully a person who has the use ofreason must be suitably instructed, properly disposed, and able torenew the baptismal promises" (CIC 889:2). For this instruction yourparish may put you in an RCIA class for the sake of convenience.You do not need to receive confirmation before beginning to go toconfession and beginning to receive the Eucharist. Nothing in canonlaw requires that, and you may begin practicing those parts of aCatholic's sacramental life as soon as you have understood andaccepted the Church's teachings concerning them. If that doesn't work, RCIA is your only bet.(the information below is about RCIA and is taken fromhttp://catholicism.about.com/cs/education/a/RCIA03.htm)Most Catholic parishes have classes to prepare people to convert toCatholicism. These classes are called Rite of Christian Initiation ofAdults or RCIA. The conversion of Catholicism is a gradual one.Students are asked to pray and study scriptures. Also, they learn the catechism.The RCIA classes are usually held every week. At these classes, youwill learn the fundamentals of Catholicism. As you learn, you will seethere is much to learn about being a Catholic. RCIA contains fivephases.The Period of Inquiry ? This is when people can ask questions to getan idea about Catholicism. They learn about scriptures and JesusChrist. This period takes as long as it needs to. When the person isready to go to the next phase, sometimes they need to write a lettersaying why they feel they want to convert.Period of the Catechumenate ? For this phase to begin, people need toaccept Jesus Christ is their savior. They begin going to Mass onSunday and further their commitment to the faith. They reflect moredeeply, about how Catholicism will affect your life. This phase alsolasts as long as it needs to for individuals.Period of Purification or Illumination ? This period corresponds withthe time of Lent. It is the six-week preparation time for Easter. Itbecomes the praying time for those who are to become Catholic known asthe Elect. The period is begun by the Rite of election, usuallycelebrated at the Cathedral Church with the Diocesan Bishop. This riteaccepts them accepted as candidates for the Sacraments by the Bishop,representing the fact that this decision is not theirs alone. Normallythis rite takes place on the first Sunday of Lent. Special prayers areoffered to support the Elect.Celebrating the Sacraments of Initiation ? The Sacraments ofInitiation is celebrated at the Easter Vigil. The Easter Vigil is anextended night watch of prayer, singing, and hearing the Word of God.By the waters of baptism, a person passes into the new life of graceand becomes a member of the Body of Christ. Those who are all readybaptized, have the Sacrament of the Reconciliation prior, are givenHoly Communion, and are confirmed. Anointing with Holy oil calledchrism seals the initiation by the power of the Holy Spirit andparticipation at the Table of the Lord in the Eucharist marks fullmembership in the church.The Period of Mystagogy ? This period lasts from Easter Sunday untilthe completion of the Easter season. That is fifty days later onPentecost Sunday and completes the initiation process. Those who havejust shared in the sacraments of initiation are now called Neophytesand during this period of Easter joy they reflect on what they havejust gone through and look to the future as to how they can now sharein the mission of Christ who came to bring salvation and life to thewhole world. This period reminds the whole church that life in Christconstantly calls us to grow and to look for new ways to live the lifeof grace, personally and together.If you were already baptized, you probably won?t need to be baptizedagain. You will need to the Sacraments Reconciliation, Holy Communion,and Confirmation. Most RCIA programs last about a year. This varieswhere you are from and whatever that particular parish chooses to do.In most cases, people who all ready had their Holy Communion areconfirmed in June with others from the diocese.