vatican.va/holy_father/leo_xiii/encyclicals/documents/hf_l-xiii_enc_10011890_sapientiae-christianae_en.html
Read, my friend. Read. It outlines quite well what we are discussing. You cannot be fully Catholic and yet allow intrinsic evil. Protest must be given. The Church declares abortion and gay marriage as intrinsic evils. They do so dogmatically. You, as a Catholic, are obliged to accept this, at the very least through obedience.
Also, a quote from the mentioned encyclical:
“But, if the laws of the State are manifestly at variance with the divine law, containing enactments hurtful to the Church, or conveying injunctions adverse to the duties imposed by religion, or if they violate in the person of the supreme Pontiff the authority of Jesus Christ, then, truly, to resist becomes a positive duty, to obey, a crime; a crime, moreover, combined with misdemeanor against the State itself, inasmuch as every offense leveled against religion is also a sin against the State.”