The 19-year-old model said "she was lost in darkness".
"There are so many moments I have taken for granted in this life due to my lack of presence. I have overlooked countless blessings and opportunities to start fresh, and I have neglected, manipulated, and lied to the people I hold dear to my heart, but more importantly, to myself.
"It hasn't been until recent months that I relearned what it truly means and what it feels like to be fully present," she wrote on her Instagram account.
"I was so lost in darkness, that I could hardly hold a real conversation with another human being long enough before I was due to have an anxiety attack and find my way out of it. (sic)," she added.
Ireland also admitted she has taken a hard look at the last few months, insisting she is lucky to have met "the most phenomenal souls".