Why can't the question "Was life better before the revolution?" ever be answered?
Winston tries desperately to remember for himself what his life was like but he can only get back so far before his memories recede into the distance. He also has to be careful how and where and when he asks about it because if a Party member knows, it will certainly be considered thought-crime.
The Party has gone so far as to attempt to destroy any remaining records from before the revolution and even the proles have been rendered incapable of remembering anything significant no matter how hard Winston pushes him or how many drinks he purchases for him.
Winston himself is involved in the selective editing of anything from the past that doesn't conform to the ideas of the Party and the efforts at erasing the past have been quite successful.