"I realised art was as important to me as the medical processes I was going through.
"I had talents and abilities and I had to use them."
Mary, 51, a graphic designer, teacher and book publisher, said when she showed people her art and writing they often were entertained and always interested.
"Some were done when I was very down and out and black with depression but a lot are very bright and happy," she said.
"1t opened up a connection with people. I had nothing to lose. I was no longer embarrassed or worried about what people think about the work I had done."
From Pain to Power is an exhibition of some of her artwork which was opened on Friday night by Christine Clifford, a psychologist at the oncology ward at the Royal Hobart Hospital.
Mary hopes to produce a book next year as a part of her masters degree in fine art and design.
"I've found expression is extremely important and that you can cry on anyone's desk," she said.
As to her health, she says she is fortunate.
She is regaining her energy and her hair is growing back after she lost it during the chemotherapy sessions.
From Pain to Power is a the Sidespace Gallery at the Salamanca Arts Centre until November 13.
She will talk at Women Tasmania on November 20 from noon to 2 pm.