154. We also know that, within marriage itself, sex can become a source of suffering and manipulation. Hence it must be clearly reaffirmed that “a conjugal act imposed on one’s spouse without regard to his or her condition, or personal and reasonable wishes in the matter, is no true act of love, and therefore offends the moral order in its particular application to the intimate relationship of husband and wife”.(Humanae Vitae 13)
A humanist perspective:
The acts proper to the sexual union of husband and wife correspond to the nature of sexuality as
willed by God when they take place in “a manner which is truly human”.(Gaudium et Spes 49)
Saint Paul insists: “Let no one transgress and wrong his brother or sister in this matter” (1 Th 4:6). Even though Paul was writing in the context of a patriarchal culture in which women were considered completely subordinate to men, he nonetheless taught that sex must involve communication between the spouses: he brings up the possibility of postponing sexual relations for a period, but “by agreement” (1 Cor 7:5).
Remember that Amoris Laetitia is online here.