open one's heart to
open (one's) heart (to someone)
To share one's deepest or most intimate emotions, thoughts, or secrets. Samantha finally opened her heart to me last night about how grief-stricken she's been since her father passed away. My father was a cold man, and he never opened his heart to anyone.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
open one's heart to
Confide in, reveal one's thoughts and feelings to, as in Last night Meg opened her heart to her sister concerning her marriage. This expression uses heart in the sense of "the seat of thought and emotion," a usage dating from the 9th century.
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.