Shadows of the Night by Evie Bennet

The joy of new beginnings is cut short when Betty and Reed return home from their honeymoon to a mysterious package and a PI hot on their heels. When Betty, with the help of the Rattlers Motorcycle Club, discovers who sent the PI, her world is rocked.
The chaos threatens their stability and new family. Betty will do anything to protect her new life and love, including risk reconnecting with old ghosts at the expense of her sanity. And Reed will do anything to protect Betty.