Looking for this book
NEW ADULT AGE GAP Romance SERIES. SWEET & SMART HEROINE with abusive family FALLS FOR OLDER SISTER’S RICH BOYFRIEND IN MILITARY? THEY WRITE TO EACH OTHER SPOILERS AHEAD.
Not sure date of publication but I read in 2020 on Amazon
A teenage girl, the heroine, falls for her older sister’s boyfriend, the Hero. The girl’s family is really crappy to her, including the older sister (also drinking, drugs, abuse mental and physical of h by whole family, basically white trash).