Born on February 29, 1944 in Devils Lake, North Dakota, Frelich was born to deaf parents and was the oldest of nine deaf children. She attended the North Dakota School for the Deaf and graduated in 1962.
Frelich's stage work included "Sganarelle" and "Songs From Milk Wood" at The National Theater of the Deaf. She was also seen in "Big River" and "Prymate" on Broadway. Frelich won the 1980 Tony award for Best Actress in a Play for her work as Sarah Norman in "Children of a Lesser God."
Frelich appeared in the daytime soap opera SANTA BARBARA as Sister Sarah in 1988.