As we reported earlier this week, Ariana Grande began Big Sean are dating shortly after both were involved in high-profile breakups.
Now it seems that the longtime "friends" and musical collaborators may have kicked off their romance while they were both still in relationships.
Sean's ex Naya Rivera married Ryan Dorsey last month (on the same day she was supposed to marry Sean), but sources say she's still devastated.
Naya reportedly can't get over the fact that Sean and Ariana are in a relationship, and she's now convinced that the rapper cheated on her with Ariana.
"It's her worst nightmare because she was always sure that Sean was cheating on her with Ariana," says an insider close to Naya. "They fought about that a lot."
"Sean would tell her she was crazy and jealous. He swore to her that Ariana was just a friend. He even said she was like a little sister."
Naya, however, isn't buying his lines and "feels like this is proof that she was right all along and Sean was hooking up with Ariana."