The 26-year-old singer's mental health struggles stopped her from "thinking normally" about life as she was constantly worried she and her loved ones were going to die.
She admitted: "If I look back at the last seven to 10 years of my life, I can't remember them, that time in my life is gone.
"Anxiety almost blocked me from thinking normally and remembering things, because I was so anxious about everything," she continues. "I thought I was going to die; I thought my family were going to die and that was mixed with a lot of things like OCD, which added to the anxiety as well. I regularly found it hard to leave the house."
The 'Perfect To Me' hitmaker tried various forms of therapy, which were helpful, as was Googling how she felt.
She told the April issue of Glamour's digital magazine: "I've literally done everything that you can do.
"I tried therapy, hypnotherapy. Googling about anxiety helped a lot and listening to other people's stories. I think hypnotherapy was really a big part of it. I guess talking and listening to other people helped."
Therapy has taught Anne-Marie to verbalise her worries as it makes them more "normal".
She said: "As soon as I say something I had been thinking, it makes it feel normal.
"In my head, the thoughts are so bad and then as soon as I say them out of my mouth, it's 25% of how bad I thought it was going to be."
Although she's in a much better place now, the singer still has "bad days" and doesn't feel fully recovered yet.
She said: "Honestly, I feel like I've not [fully] got myself out of it yet. I've relied on a lot of people to help me, which is why it's so important to talk about it, because hopefully I'll be that person to someone else, like how other people were there for me.
"Now I can actually walk into rooms first, before anyone else, which is great and I can answer the phone, which I never used to be able to do.
"I have bad days too. But at least it's only a day now, whereas before it was all the time, so that is where the improvement is. It's going to be a constant battle, but to know that it'll be OK is the best feeling."
Read the full feature in the April Digital Issue of GLAMOUR, available online now.