scar tissue

arpikudos puhekieltä A type of tissue found in animals containing a higher than normal amount of the protein, collagen, formed in a place where an injury has healed.
By extension, the abstract feeling of their being long-term consequences of a negative event.
2010, Kevin Leman, Sheet Music: Uncovering the Secrets of Sexual Intimacy in Marriage, page 32:

So many people's lives have many broken relationships that have left behind psychological scar tissue.