Jenelle Evans, 23, broke off her engagement to Nathan Griffith in July

By Michele Corriston
Updated August 21, 2015 01:00 PM

Jenelle Evans looks stoic and somber in a new mug shot following her arrest Thursday after allegedly assaulting her ex-fiancé’s new girlfriend.

On Friday, police in Horry County, South Carolina, released a photo of the Teen Mom 2 start after she was booked.

Evans, 23, broke off her engagement to Nathan Griffith – the father of her 1-year-old son Kaiser – in July. The two are frequently depicted fighting on the MTV reality show, and things reportedly took a violent turn again this week.

Griffith’s 29-year-old girlfriend claims Evans hurled a glass at her head, and she has been charged with assault in the third degree, according to local news station WBTW.

Evans was arrested in May in connection with domestic violence after allegedly attacking Griffith.

She has another son, Jace, 5, from a previous relationship.

Evans spoke about her past personal struggles in an interview with PEOPLE last month.

“My life has changed so much since I stopped doing drugs – my whole attitude has changed,” she said. “I’m more active in my children’s lives, and I want to be at every milestone and special event they have. Being there for them is more important to me than going partying or doing drugs.”

Teen Mom 2 airs Thursday at 10 p.m. ET on MTV.