The actress nearly died behind the wheel while racing a friend on her way to a concert years before she found fame and success.
Cruz, 32, was hospitalised in Thousand Oaks, California and underwent emergency brain surgery to save her life.
"They had to shave my head right away," she tells People magazine, while fighting back tears. "I had a kidney contusion, a collapsed lung, and two broken vertebrae. So my eyes were crooked and my face was crooked, I couldn’t smile."
She spent 72 hours in a coma and woke up from sedation two weeks later.
"Looking at myself in the mirror, not, like, recognising myself, was scary," she recalls. "I wanted to commit suicide at the time because all I ever wanted was to be an actress and a singer and I grew up just watching beautiful people on TV and I just felt like that was it for me."
"It didn't look like me anymore. I didn't know who it was. I was very depressed and I tried to kill myself a few times with pills."
A little girl in the hospital helped Jackie come to terms with her accident and taught her how to love herself again - and now she's paying tribute to her with her first single, "Melly", which is released on Friday, March 22.
"She was 10 years old, and her name is Melly," she explains to the outlet. "She will never walk again, but she is strong and happy and she would come by my room all the time and I never really paid attention."
"Then we got to talking, and she told me I was pretty. She taught me that beauty is always from within. It's the way you treat someone, it's the way you are, and she saw that... She saw the beauty in me without looking at my surface."
Cruz admits the new song is "kind of freeing me", adding, "I've been wanting to share this for a long time, but I've been holding it in because I know that it's special and it just has to be right."