Goss said she "100% believed" that the teen was responsible for her son's death.
"He was the happiest, most joyous child until he met her, she was mean to him, controlled him and took advantage of him," she said. "Even after I repeatedly told her to leave him alone."
Benz, a student at Bothwell Middle School, began secretly dating the 13-year-old girl after he bought a cell phone without his mother's knowledge, Goss told the New York Post.
Goss told BuzzFeed News that it went on for about five to six months, but that she was "100% against it" due to their age difference.
Goss alleged that the teen "did a prank that made it look like she killed herself and used other friends and their [social media] accounts to make it look like she killed herself."
"So, [Benz] believed her and said, 'I'm going to kill myself,'" Goss told the Post.
Goss described her son as a "student, athlete, comedian, friend, brother, charismatic and all around amazing child."
"I urge families to speak out, reach out and communicate with your children about life's precious gift and the dangers of the internet and texting and how telecommunications can have the same effects as speaking face to face," she said.