When you get taken by Death Eaters Severus reacts just as you could imagine. He loses his shit, and he loses it hard. Albus was the one who told him that you went missing the night that Severus had told him the Death Eaters would try and get into Hogwarts. He started breathing heavily and was struggling to hold in his panic. You were his last chance at happiness and his stupid past was trying to take it away again. Dumbledore could see this and said that he would gladly join him in fighting to find you. He got the order together in his office and sent them out in groups of two to look all over the country to look for you. They couldn't have taken you too far as they probably wanted to use you as a deal for Harry or something. Severus went on his own to look at Death Eater locations and see if anyone was talking about you. The amount of anger he felt when he heard Malfoy talking about what he was going to ask Bellatrix to do to you next.

He sent a message to Albus who informed everyone else about where you were and your condition. Severus was asked to stay behind as if he got seen trying to get you out, the plan would be ruined. He hated it. He hated that he couldn't end the lives of the people hurting the last chance at love he had left. But he had to listen to Albus. Your life was at the stack and if he barged in they would easily take you again for leverage against the order. When Arthur walked out with you bleeding in his arms Severus had to hold back the tears forming in his eyes that some of the others couldn't hold back. Once you get back to Hogwarts he begs Albus to let him treat you in his quarters and after some talking with Pomfrey you're locked in his room with bandages covering nearly every piece of skin that was showing. While Severus was treating you he was crying... and drinking. So when you first woke up you noticed him drunk in the chair beside you muttering something as you fell back asleep.