My great-grandma was born in 1935 in what is now Constanța County, Romania, then a kingdom, became communist in 1947. Broke up the family of her mom’s wealthy employer (mom was a maid at his beach vacation house) in order to marry him in the early 1950s and move to Bucharest, cheated on him with an even wealthier guy (this guy was wealthy from illegal means - black market; wasn’t a party member) / marries this dude, she becomes an informer for the Securitate (political police) and helps get him arrested, tortured and imprisoned when the system has had too much of him so she gets off scot-free in the 1980s and marries another wealthy guy (this time a wealthy higher up party member) who capitalizes on the regime change post-1989 (Revolution) to become filthy rich in the new capitalist landscape. In the 2000s this guy becomes ill and allegedly she had a part in him dying faster than he should’ve, inherits a fortune. Moves to Switzerland where she gets an younger boyfriend with whom she’s with to this day. She’s 90 now and faced no repercussions for her actions; lived a luxurious, leisurely, carefree life, never worked a day in her life.
I believe karma exists, but it’s decided by each person for themselves. If you have guilt about something, you’ll find a way to punish yourself or surround yourself with people who will. If you’re a narcissist and/or are too stupid to have guilt, you will seem to get off with no repercussions. In the end though, the people with no guilt, also can’t feel. Life tastes pretty bland, so that’s a punishment in itself.
TL/DR: Make peace with person/people/yourself on things you feel guilt about.