take something off my chest
Meanings of "take something off my ..."
With all due respect, the actual idiom is "to GET something of one's chest"
If someone gets relief by confessing or communicating something that has been causing a negative feeling (guilt, worry, frustration, anger, etc,) then she "got it off her chest".
"I have to get something of my chest, son, I am sick and tired of your crashing all the family cars."
"Finally she got it off her chest that she was in love with her sister's husband."