Consistent episodes of domestic violence caused Demi Lovato's mom, Dianna De La Garza, to divorce her biological dad, Patrick Lovato, but the details about their relationship are simply horrific. In an excerpt of Dianna's new memoir — obtained by PeopleFalling with Wings: A Mother’s Story, she recounts a period in 1988 when Patrick's substance abuse problem took a turn for the worse.

Patrick slammed a door so hard on Dianna's hand that she lost a finger, but despite the incident, she stayed with him. She said, "I thought I could change him, and I think victims of domestic abuse often feel the same way. You're not always going to be able to change someone, no matter how much you want to."

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Ultimately, the 55-year-old looked for guidance at a women's shelter when she made the decision to get out of the relationship in 1994 — Demi was 18 months old and her sister, Dallas Lovato, was six. She said, "I didn’t know how to leave, and I didn't have any money. I would call them [the shelter] every day and talk to them, trying to gain the courage."

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Dianna did gain the courage when she came to the realization that her young daughters weren't safe. She said, "When I realized they were not safe anymore, no matter how much I loved this person and wanted things to change, I knew I had to get out."

One year later in 1995, Dianna married her current husband, Eddie De La Garza, and in 2001 they had their daughter, Madison De La Garza. Eddie has not only been a present father figure in Madison's life but in Demi's and Dallas' as well.

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The "Tell Me You Love Me" singer walked the red carpet with Eddie at the Grammys last year and when [Entertainment Tonight](http://www.etonline.com/awards/grammys/210203exclusivedemilovatodadjoinsheronredcarpetasgrammysdate) asked who she brought, Demi said, "[I brought] my dad, he's right here!"