Dwindle by K. A. Gandy

Torn from her home and family. Forced to marry a genetically matched stranger. Will she find love, or destruction?
Sadie yearns for the loving marriage her parents share. But with the Sterilization Vector threatening human existence, she despairs she’ll be mated solely for her genetic compatibility. When she’s torn from her home and family and forced to marry a man she’s never met, she’s at risk of losing her dream forever.

Thrust into the compulsory marriage program, all is not as it seems. She’s shocked to learn that she has an unprecedented number of matches to contend with, some of which don’t have the best of intentions. Could her genes hold the key to unlocking what remains of the world’s reproductive potential, or will she be one more woman swallowed up by humanity’s collapse?

If you like dystopian reads with heart and a hint of romance, you’ll love this story.