Say if a Lutheran married a follower of Benn Hinn -- there is a difference of opinion and of belief. There can be conflict, but doesn't have to be if both partners go into the marriage knowing the differences and accepting it
A cousin of mine married a Hindu and they've been married for 15 years, happily.
Even among Christians -- if a CAtholic marries an Orthodox or a Lutheran, the differences as not as acute as say for a Lutheran to marry a Baptist
I've never heard of any one being advised, once they have decided to marry, against marrying a non-Catholic
All that they are taught during this pre-marital course is "recognize the differences and accept it, or don't get married" -- and it's not only religious differences, but also other topics -- children, money, living with the family etc. -- people should go into marriage KNOWING about the other person and accepting it -- if a Catholic/Lutheran marries say a Baptist, then the Baptist should recognize that the Catholic will go for mass and that the Lutheran believes in the True Presence of Christ in the Eucharist
They don't have to believe it, but accept that their partner does. Otherwise, it is not going to be a successful marriage.
Taken from:
--"My Catholic Faith - A Manual of Religion" by Most Reverend Louis LaRavoire Morrow, D.D., Section 166 - Church Laws on Marriage (pp 344-352), (All material from "A Catechism of Christian Doctrine, 3rd Revised Edition of the Baltimore Catechism, 1954").
Are you saying that something changed between 1954 and now? Can you please refer to the document or decision that changed this?