It strikes me that the issue really can be boiled down to a question of whether one believes that Christ established his Church on earth (Mt 16:18) and that it possesses infallible authority in matters of faith and morals.
If one does accept that premise, he or she must accept and observe those teachings.
If one does not accept that premise, they cannot say they are Catholic as they, ipso facto, dispute the Church’s authority on such matters. By definition, they are Protestant.
Personally, I recognize that some of the Church’s teachings can require sacrifice, but I accept that the Church is His Church and must accept its teaching on these matters.
All protestant churches held contraception to be a sin until 1930. Did God suddenly write a new book of the bible then? No, the Anglican church bowed to social pressures and decided to ignore the bible and 2000 years of theological teaching and thought.
The Roman Catholic Church’s stand on this is very well thought out and documented and justified. While it may be inconvient for the modern social mores, there argument is in every way I can examine it, airtight.
The Church isn’t wrong on this one, men and women just act in selfish ways, which is the nature of man. When they do, and those selfish acts are challenged by the church, the natural reaction is to say the church is in the wrong. This however is rarely the actual case.