Leah Messer says goodbye to her three daughters on Thursday's new episode of Teen Mom 2.

Leah Messer On Entering Treatment: 'I Felt Like Things Were Spiraling Out Of Control'

After failing to file through with her initial plan for treatment on last week's episode due to her fear of losing custody, Messer decides to begin a treatment program, which will keep her from her daugthers for three weeks.

"I'm leaving for therapy really early tomorrow morning, so I'm staying a hotel tonight [and] my mom will bring the girls to Corey's this weekend," Messer tells viewers in the MTV sneak peek at next week's show.

Corey Simms Shares Elaborate Message On Twitter Explaining His Allegations Against Leah Messer

While Messer denies her decision to enter treatment was drug-related, her ex-husband, Corey Simms, the father of her twins, Ali and Aleeah, 5, told her weeks ago he felt she was hiding a "drug problem," and on Twitter, he explained his allegations.

"There is a reason for everything that Miranda and myself have said or done. We simply want the girls to grow up in a safe and healthy environment," Simms wrote last Friday morning. "There is a lot of things that has been told to us by very close members of her family that lead us to believe the things being told are very much true. If we didn't care about the girls or the situation we would obviously not have anything to say or do about it. Thank you to the people who understand and to the people that don't well that just sucks now don't it?"

For more Leah Messer, tune into Teen Mom 2 season six on Thursday nights at 10 p.m. on MTV.

Tags: leah messer Teen Mom 2 MTV Reality TV Corey Simms