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.
See also: unburden
Farlex Dictionary of Idioms.

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.
See also: unburden
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • unburden
  • unburden (oneself) to (someone)
  • get a grip of (oneself)
  • get a grip on
  • get a grip on (oneself)
  • get a grip on yourself
  • get/take a grip/hold on yourself
  • bear the burden (of something)
  • burden
  • keep a level head
References in classic literature
It's very seldom I talk as plainly as this to any, one but you are just the person one can unburden oneself to a little; and to tell you the truth, it's rather a relief.