Silo Saga: Silo 1000 by Michelle M. Pillow
Trapped in an underground silo because the air outside is too toxic to breathe, the people of Silo 1000 are very aware they’re only one of many such self-contained units. Human survival is top priority as they wait for the day they can once again walk the earth.
In such a reality, Maryann Holston never bothered trying to fall in love. She knows she’ll have to take whatever fate the silo thinks is best for the betterment of all. But as she runs into childhood friend, Paul Allison, she realizes that maybe love is exactly what her life needs. No longer the lanky boy from her youth, Paul is everything a woman could want and she intends to be his wife…until the unthinkable happens.
There are those who will stop at nothing to make sure Maryann is out of the picture–permanently–and Paul’s ready to prove he’s willing to do anything to save the woman he loves.