Germans hated the red army and the soviet union. Due to the nature of fighting on the eastern front, and the cruelty to which both sides treated each others soldiers, hundreds of thousands of German troops who had surrendered to the soviets were killed. Towards the end of the war when the red army reached East Prussia they systematically raped, pillaged and tortured the entire populace, a pattern which they continued across all of Germany. The German population overwhelmingly hated and feared the USSR, when the war ended, huge numbers of people in all the Soviet occupied areas of Germany held massive protests against communism. These protests were only ended by violent intervention from the USSR.
"Were they happy that the Third Reich had be overthrown?" The extent to which Germans liked the Third Reich is highly debated to this day. I believe the arguments that, while hitler may have been unpopular for many decisions, most people in Germany either liked or were fairly indifferent to the Nazi party. The decades following WW2 many anonymous interviews were carried out across Germany, to see how they saw the Third Reich. One of the most common themes was that the Third Reich prior to the War was an almost paradise.
It has to be remembered that Germany was facing an endless multitude of social and economic problems prior the Nazi party taking control. Germany had huge numbers of homeless people, high crime rates, high levels of unemployment. For the average German citizen these problems vanished almost overnight as a result of the Nazi's. The congregations of dodgy homeless drifters and robbers that lurked in cities were simply loaded into Nazi trucks and vanished out of sight. The people who had terrorized ordinary German people ceased to be a problem thanks entirely to the Nazi's, as such, The third reich was pretty popular prior to the war.