While many "General Hospital" fans criticize Nina Reeves for her oft-impulsive decisions, she was justified in turning Carly in for her crime because Carly is mean-spirited and treats her like dirt. But Lois doesn't have that excuse. All she heard was that a secret was kept from Sonny Corinthos — like not knowing Dante was his son — and she ran right to him to blab it all without fully considering the consequences. She, Olivia, and Sonny all grew up together in Bensonhurst, and she failed to trust Olivia's justifications.
Nina has finally made a connection with her long-lost daughter Willow Tait (Katelyn MacMullen), and they're in a good place. She also makes Sonny happy. Plus, Ned now has Michael's control of the family business ELQ, after he and Michael made the deal to keep quiet about Nina's actions. Olivia tried to warn her best friend about the damage the truth would cause. This was not Lois' secret to tell, and she pretty much sacrificed her friendship with Olivia and flushed Nina's relationships with Sonny and Willow down the toilet.
Olivia asked Lois to trust her, but she just did what she wanted, consequences be damned, and she'll probably go back to Bensonhurst after dropping this major bomb in Port Charles. It's unclear how long Rena Sofer is going to be on "GH," but hopefully it's long enough for her to try and repair her friendship with Olivia.
