I don't think that they have ever had a history of him lying to her. Quite the opposite from their posts to this point. Genebean his a past history of being made to feel less than, unwanted, etc, by other people prior to her relationship with Polypenguin. She has said that her trust issues come from her own personal issues, not to do with his behavior. At least up until now.
At the beginning of my relationship with Wendigo, I had him over while Runic Wolf was out of town. I'd had blanket permission to do so with anyone I wanted to be involved with, but it was my first time taking advantage of it. When he got home, a friend of ours had just gotten into town, was waiting for us at our usual meet up for dinner, and I still wasn't sure what I was thinking or feeling about the hour I'd spent with Wendigo the day before. So when Runic Wolf asked what I'd done while he was away, I lied. . . . at first I glossed over the truth. I talked about talking to friends online, how much I'd missed him, etc. And he kept asking me and I wanted to get going to dinner, so I told him I'd done nothing. I had permission and I still lied because I wasn't done processing and didn't know how to explain that. And that lie ruined dinner, because Runic Wolf could smell him on our bed, could tell I was hiding something, and ultimately I hurt him deeply and we went through a year of rebuilding trust over one sentence.
I do understand Polypenguins upset at her reading his blog b/c he specifically asked her to give him a space to process what he was going through when he obviously feels like he's making a sacrifice while she's getting to explore, even a little bit of what it is to be poly while he's still waiting at the starting line. No he shouldn't have lied, but she shouldn't have read his blog either if she's agreed not to.