I've had the same problem when playing a multiplayer game. We created the multiplayer game from the beginning so that we could both create our own unique characters, which worked great and was super fun. The problem was experience sharing. The other player was the host of the session but for some reason, even with them standing beside me in game, I was the only one gaining experience from conversations when I initiate them, which was a pretty big loss for the other player within a couple hours of play, I'm nearly a full 2 levels ahead of them. I was the parties dialogue initiator because I have high deception bonuses and that's the path we were choosing to play.