The 31-year-old "The Bachelor" and "Bachelor in Paradise" alum recalled in an Instagram post Wednesday the "months of anxiety and depression" she experienced during a time of "pain and scarcity" in 2018.
Nielsen reflected while reviewing her bank statements and every single transaction in 2018.
She said she had "a year of extreme lows and highs" after accruing $12,000 in hospital bills, which lowered her credit score to 620.
"2018 was the year of breakdowns and rebuilds," Nielsen wrote.
"I could see and feel the pain and scarcity as I went through each statement - the overdraft charges, the credit card payments. To look back and relive some of the toughest moments in my life, the moments when I doubted myself the most."
"When I came across the hospital bills I had a flashback to the phone calls from my friend Heather about how I needed to confront these heavy bills rather than pretending that they didn't exit," she said.
"The heavy slap of defeat. The months of anxiety and depression. The confrontation that I had failed and fallen and didn't know what pieces could even be put back together."
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Despite her financial setback, Nielson said she pursued her dream of writing a workout program and launching her own business. She sold her first copy of Total Body Guide in March 2018.
"I watched the fall and rise. The come up. The dark nights and heavy storms my heart endured," she wrote.
"Looking back I now see that those thunderstorms are the reasons my dreams blossomed. And my tenacity, inner strength and beliefs reflected through every purchase and transaction."
"2018 You taught me that my heart is the only validation that I need," she added. "To embrace the dark nights because that is when we grow the most. And most importantly to never lose faith in my dreams."
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