Welch, worked as a dancer for the Jonas Brothers band, and Lovato was opening for the act in a South American tour when an the altercation broke out on a flight out of Peru.
Lovato allegedly confronted the dancer because she thought Welch had told tour management about Lovato’s heavy night of partying.
Lovato punched Welch, but Welch did not fight back. Shortly afterward, Lovato checked herself into the Timberline Knolls Residential Treatment Center near Chicago.
She reportedly is dealing with anger management issues and a cocaine habit.
The official explanation is “emotional and physical” issues, not drugs.
But so far an apology is not part of the treament.
“To this day, I haven’t gotten an apology. I’ve heard nothing,” Welch told People. “That’s sad if you think that person is your friend.”
Welch, 21, said Lovato was upset because she had “gotten in trouble” over antics on a night out.
After being confronted by tour managers, Lovato “pulled the dancers in a room and threatened: ‘If I find out who told on me…'” Welch said.
“We were on the plane with the Jonases having this awesome time and I didn’t get a call or text from Demi or a ‘Hey, you got a problem with me,’ nothing.
“And she walks up and punches me and literally walked away and got in her seat.”
‘No one should walk up and do that and brush it over, it’s not right,” Welch adds.