This tremendously insightful summary of the relationship of the religious life to married couples comes from The Christian State of Life by Hans Urs von Balthasar:
Thus both states [the "lay state" and the "religious" state] live by the same love: the love of Christ, which is the paradigm of every love. And both states are fruitful by virtue of this love because both bear in themselves the principle of fecundity—namely, love itself which is poured into our hearts together with faith and hope. For God was not content just to surprise husband and wife by a reward bestowed on them from without; it was also his will that the fruit of grace should issue in them from the love he had bestowed on them as their own: as their fruit and, at the same time, as his fruit for and in them. The more closely human love resembles God’s love, the more it forgets and surrenders itself in order to assume the inner form of poverty, chastity and obedience, the more divine will be its fruit: a fruit that surpasses all human fecundity or expectation. This fruit is bestowed in its unity on the state of election, which renounces by vow not only its own physical and spiritual fruit, but also, and more significantly, the privilege of seeing the fruit God may choose to send it. It abandons to God at the same time both its whole self and the outcome of its total self-surrender. For the Lord on the Cross did not see the fruit of his gift of self, but rather placed it in the Father’s hands so that, after he had risen from the dead on the third day, the Father might return it to him superabundantly. Christian marriage likewise shares in this fruit, both by the sacramental vow that leaves a priori to God the decision as to what physical and spiritual fruit he may choose to bestow and by being satisfied with whatever decision he may make. If Christian spouses are able genuinely to make this act of perfect self-giving, their limited community is opened to the universality of the Catholic Church, and their love, which seems to be focused on so narrow a circle, is enabled actively to participate in the realization of the kingdom of God upon earth.
Nevertheless, the Christian remains in all this a "layman." He is not transferred even by this special christological sacrament into the state of a qualitatively higher vocation. His life-form is not one that was newly instituted by Christ, but rather one that was already valid under the Old Testament and was supernaturally raised by Christ to the dignity of a sacrament. He is still bound to a form of physical self-giving that attains only in exceptional cases to a perfect resolution of all guilt-caused concupiscence. He cannot transfer to his children, who in their turn were born into the corruption of their race, the sacramental grace that has blessed his own marriage. Nor does his state confer on him the right to complete, in poverty, chastity, and obedience, the perfect holocaust, not only of the spirit, but also of the body, to which those in the state of election are called. This does not mean that he is a less worthy Christian than they are, for, even when God's gifts vary, his election bestows on each individual only what is best. Both states—the lay state, which achieves its fulfillment in the married state, and the state of election—condition one another and are intimately related to one another; not, however, as two equal and complementary halves are related, but as the special state, which emanates from the general one and returns to it by way of sacrifice and mission, is related to the general state that is a genuinely Christian state only because of the special state. This relationship reflects the basic law of the economy of salvation: that the Old Testament is both continued in and surpassed by—both incorporated into and superseded by—the New Testament; that the New Testament complements the Old Testament, yet is itself so new that only could have seen that it was already present in the Old Testament.