Will and Nico have been dating for about two years. Recently, Nico has spent the last two months traveling to help bring new demigods safely to camp. He left knowing he would be gone for a while, and everyone—including Will—expected it. This wasn't another dangerous mission or the result of one of Nico's guilt spirals; it was a normal assignment, and Nico had said goodbye before leaving with every intention of returning when it was finished.