Minako nodded at Rei when she mentioned having sensed Usagi. So it wasn't just a wild theory the Senshi leader had to try and make sense of what had just happened. Usagi really had been there. The ice was there, but Minako knew better than to be this way when they were trying to reach the girl who was trapped inside Serenity. So she followed after Rei who had gone after Serenity, listening to the words spoken, seeing the ghost of Usagi apologize to them about being unable to. While she had vanished and Serenity had spoken, Minako had something to say to Usagi, though it did tie into what Rei had said to Serenity.
"Usagi, I know you can hear me. You may think you can't, but you're stronger than you let yourself believe, stronger than all of us. You need faith in yourself because we have it for you and we're waiting for you."
And then there was Serenity to contend with. Her word choice certainly was interesting. Beryl had awakened her this way? And just how did she mean that? Endymion had been hurt and Usagi had awoken as the princess only without her memories. It was when he was being taken that Serenity truly came to the surface. But Beryl hadn't done anything to awaken the princess. Not on purpose at least. So unless she meant in taking Mamoru, this was all Beryl's fault....
Disgusting. Rei thought Minako more tactful in her words, and she was, but she also thought this entire thing disgusting. And of course she'd place blame elsewhere.
"As Rei said, Usagi is stronger than you think, stronger than you. Do you want to know why that is? It's because she wasn't afraid to do what she had to in order to protect this planet. She allowed herself to break her own heart to do what she needed to do to save everyone. You, though? You wish to destroy everything she fought so hard to protect and even though she's hurting, she still cares about her friends. It's that caring that makes her stronger than you. You can claim this is Beryl's fault but you could still fight it if you really wanted to."
Was that the thing to say? Maybe, maybe not. Dealing with Serenity was always a gamble. But the fact remained that it was true. And Usagi needed to hear it as well. She needed to know that she was strong and the reasons for why that was. Yes, her words were directed to Serenity, but it was clear that Usagi was beneath the surface. She needed to know she wasn't alone.