Duke would've asked why, or even how, but for once, this was a Haven Moment that he was willing to just let happen.
He was sitting in his truck, which would normally be fine, but he could tell it was after Audrey had talked Aiden Driscoll down, and he and Nathan had had their brief heart-to-heart about how Duke wasn't so selfish as to want Nathan dead to get to Audrey.
He knew this, because his past self from that day was walking towards him while on the phone–making the call to Jennifer to tell her that he didn't want her to get off the Rouge, and asking her to come back so he could try to explain himself to her. This Duke, the Duke who wasn't originally here when this happened the first time, quickly pieced together why he'd been sent to this moment, and not to one closer to the Lighthouse and losing her. He'd been given a second chance, and he wanted to do it right.
His past self had been so wrapped up in his phone call, that he didn't notice himself sitting in the passenger seat.
As he reached to put the key in the ignition, his past self seemed to finally realize that something was wrong. When he turned and looked at him, Duke already knew what he was going to say.
"What the ever loving–"
"We're having a Haven Moment and we're just going to let it happen." Duke interrupted himself quickly. He could see himself gearing up to say something more–and probably pull a gun on him (which really would only complicate this situation further but arguing with yourself when you have a gun on yourself probably won't help the situation anyway), so he spoke quickly, "You're going to kiss her."
His past self looked at him in surprise, "What?"
"You're going to kiss her." Duke repeated, "You're going to take her in your arms, you're going to carry her to your bed, and you are going to show her how you've felt about her since you first saw her."
His past self didn't say anything to that, just continued to give him a calculating look. Carefully, his past self said, "She's dead. Isn't she."
It wasn't a question, but he answered him anyway, "Yes."
They stared at each other for another moment before he added, "When you kiss her, don't stop there."
At his past self's confused look, he said, "Get her as far away from this town as possible, and don't look back. Audrey's back, you've done everything you could need to–it's time to stop being the schmuck that has to sacrifice everything good in our life."
His past self looked at him incredulously, "Why? Why not just send her away like we wanted to before and stay here?"
He leveled his gaze at himself, "Because trying to send her away ripped us apart. Because, just this once, we are that selfish."
His past self looked like he was going to ask him something else, but Duke only said, "She's worth it. And so much more."
Duke could feel a change coming, and could feel that his time in this moment was coming to a close, so he repeated, "Get both of you away from here and never look back."
And with that, his past disappeared, and he was left hoping that things had changed.