After last nights elimination show she said: "I thought I was gone. Seriously I thought I did but there were so many people voting for me I got through."
The Dubliner has since revealed the cause of near meltdown was celebrating her own birthday without her 23-year-old daughter.
"I missed my daughter so much and I missed my family. That's why I was so sad and then the birthday came and everything," said former Tesco worker Mary. "I got so low."
"It was the first birthday I have ever been away from Deborah. I spent the day doing vocal training and then doing media interviews in a big hotel in London. It was evening by the time I got back to the house to ring Deborah. We spoke for an hour. I just felt so emotional and sad being away from her."
After her Saturday night rendition of the Fath Hill classic “There You'll Be”, Mary knew she hadn't matched her strong performances from previous weeks.
This was picked up by the judges when Dannii Minogue told Mary: "I think for whatever reason, tonight you weren't in that song."
While female mentor Cheryl Cole added: "You seemed really emotional tonight, Mary, and not yourself."
However saved from elimination, Mary is now more determined than ever to give it her all next week and insisted that next Saturday she will be a different singer.
Treyc Cohen was sent home last night after she and Katie Waissel performed in the sing off.