Did I do the right thing?

For backstory, this pertains to a couple who are both my friends, one more than the other. My current best friend

and roommate, H is dating a friend, O, that I went to school with ever since we were little. They've dated on and off for 3 years in highschool and now that we are in college, their relationship had been rocky and their arguments have increased.

When H and O decided to date again, they told each other everything they did when they weren't a couple if it included the other person. For example my friend H dated another guy (forced by her family) and told O everything they did and didn't do together and every detail. Allegedly O had told her everything but in their recent arguments he blabbed too much and accidentally spilled stuff that he did that he kept from her. She let this slide twice so far.

The reason I dislike O was because the second time he called her an option but was on his knees begging her not to leave him.

Recently a friend, A, that I broke away from because of O back in high school asked to meet. She wanted to talk about her side of the story because O had essentially caused everyone to turn on her. She provided evidence and I apologized for not believing her. A told me about everything that O said about H (hard to explain but O and A were really close friends for a while until he told everyone to turn on her). The stuff I learned that O said about H made me sick to my stomach but I didn't want to ruin H and Os relationship because they were really happy together. A and I kept our mouths shut for a while but we broke the silence this morning. We both agreed that she needed to know exactly what was said of her, even if it was the grossest stuff. H was really upset about everything and told O to meet with her (both go to different universities), we were asked to go with her formoral support so we did. O confessed to almost everything and told her "to keep you, I'll apologize to A. I'll do anything you want"

As of right now, H broke up with him but she considers him her first love and is thinking of taking him back. She loves him so much that she thought about a future with him (he had told A that he saw no future with her).

Did I do the right thing by telling her this information? Was it my place to say it? I feel like I caused this, my best friend hasn't even eaten since she found out. I feel terrible and am second-guessing my decision.