The slain wife of alleged mass murderer R. Gene Simmons was thinking about leaving her husband, but worried that she could not find a job and decided to wait and “do some checking,” according to a letter she wrote to one of her children. “I don’t want to live the rest of my life with dad,” wrote 46-year-old Rebecca Simmons, one of 16 victims of a Christmas holiday killing spree near Dover, Ark. “I am a prisoner here and the kids too . . . . Dad has had me like a prisoner.” Simmons, 47, a retired Air Force master sergeant, is the only suspect in the deaths and has been charged with two killings so far, Pope County Sheriff Jim Bolin said.