purgatory
noun [ U ] uk/ˈpɜː.ɡə.tər.i/ us/ˈpɝː.ɡə.tɔːr.i/
（天主教教义中的）炼狱，涤罪所
the place to which Roman Catholics believe that the spirits of dead people go and suffer for the evil acts that they did while they were alive, before they are able to go to heaven
humorous痛苦的经历
an extremely unpleasant experience that causes suffering
I've been on a diet for two weeks now, and it's purgatory! 我已经节食两周了，真是太痛苦了！