From the catechism:
"1620 Both the sacrament of Matrimony and virginity for the Kingdom of God come from the Lord himself. It is he who gives them meaning and grants them the grace which is indispensable for living them out in conformity with his will. 117 **Esteem of virginity for the sake of the kingdom 118 and the Christian understanding of marriage are inseparable, and they reinforce each other: **
Whoever denigrates marriage also diminishes the glory of virginity. Whoever praises it makes virginity more admirable and resplendent. What appears good only in comparison with evil would not be truly good. The most excellent good is something even better than what is admitted to be good. 119"
Esteem of virginity for the sake of the kingdom and the Christian understanding of marriage are inseparable, and they reinforce each other. Why? Because if you do not appreciate one, then you are not appreciating the other. In both vocations the person is giving themselves to either a spouse (marriage) or God (virginity). If you do not think one is a worthy gift, you are saying the same of the other.
Lemme try to make an analogy. Say friend and you won two very nice cars. You gave your car to your husband so you could both use it (marriage) and she gave her car to her dad, even if it meant she wouldn’t have a car (virginity for the sake of the kingdom). If someone says that the car she gave her dad is a worthless gift (they do not hold esteem for virginity), they are saying yours is a worthless gift too and vice versa.