He returned to communist East Germany where I imagine he was treated well enough. After all, the country was a Soviet satellite and Paulus did collaborate with the Soviets after surrendering the wretched remnants of his 6th Army in the ruins of Stalingrad. He initially resisted collaborating, but changed his mind after the failed attempt to assassinate Hitler. Paulus then made propaganda broadcasts for the Soviets. Perhaps some Germans considered him a traitor, but I imagine most of them understood his decision.
After all, Hitler had effectively consigned Paulus and his army to destruction by refusing him permission to break out of the encirclement before it was too late. And then, as his situation became increasingly hopeless, Hitler wouldn't allow him to surrender. And in a transparently cynical gesture, he made Paulus a field marshal while at the same time making sure that Paulus was aware that no German field marshal had ever surrendered.
It didn't work. He surrendered the 6th Army the following day, throwing Hitler into a rage. Der Fuhrer angrily told aides that Paulus could have been a national hero and gone to Valhalla, but he wanted to go to Moscow instead. The implication being that Paulus should have fought to the death or committed suicide. Paulus saw that clearly enough and the devout Catholic told one of his aides “ I won't do this Bohemian corporal the favor of shooting myself in the head”.
