Since their episode of 16 and Pregnant aired on MTV in 2009, Maci Bookout and Ryan Edwards have grown up and grown apart — and now Maci is getting even more candid about their tumultuous relationship in her new book.

The Teen Mom OG star reveals that Ryan was her "most painful breakup" in I Wasn’t Born Bulletproof…

Maci writes, “I convinced myself that I needed to make it work and ignored a lot of red flags. It was my second love, and my most toxic relationship. When it finally ended it was painful, but I also felt a sense of relief that the relationship was over.”

MUST SEE: Hold the Phone — Is Maci Bookout Leaving 'Teen Mom OG'?!

ryan, maci, & bentley

(Ryan and Maci with Bentley on his seventh birthday. Photo Credit: Facebook)

The reality star admits she and Ryan tried to save their relationship for their son, Bentley, — who they welcomed in October 2008 —but that they eventually realized they would be better off apart.

“We tried for a little while because we thought staying together was the right thing for Bentley (after all my parents have stayed together through all kinds of ups and downs since they were teenagers),” she writes. “But ultimately we realized that being happy and apart was far healthier for our son than being miserable and together.”

MUST SEE: Ryan Edwards Breaks His Silence on Rehab After Fans Witnessed Him Driving Under the Influence During 'Teen Mom OG' Finale

Since their split, Maci tied the knot to Taylor McKinney this past October and has two children with him — Jayde, 2, and Maverick, 1.

Last month, Ryan wed Mackenzie Standifer and also checked himself into rehab. On last night's finale of Teen Mom OG, fans witnessed the star driving under the influence while heading to his own wedding.

The father-of-one has since released a statement saying, "A little over 30 days ago, I made the decision to check myself into a rehabilitation facility. I am back home now doing well, and life could not be better. Without the support of my wife and parents I would not have been able to do this. Thank you all for your well wishes."

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