unburden oneself to
unburden (oneself) to (someone)
To share one's intimate emotions, thoughts, or secrets with someone else, especially that which is troubling, stressful, or distressing. I had simply asked him how things had been, when suddenly he unburdened himself to me about all the problems he's been dealing with in work. I apologize for unbosoming myself to you like that. I just haven't had anyone to talk to since the divorce.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
unburden oneself to someone
Fig. to tell someone about one's trouble or anxiety. I didn't mean to unburden myself to you. I'm just so upset. She unburdened herself to her mother.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.