The ending is good, I'm not sure why people see it as abrupt. So many bad reviews but I'm wondering if no one paid any attention to the idea of why this is happening. Earlier in the movie they acknowledge that in some cultures hell is in the form of re-living your sins. The stuff that happens in the mansion is a reflection of those sins since they didn't save the family. In the end, the main character says that he will go back and fix this now that he remembers and knows how, yet the doctor says he will lose all his memories which means he will not be able to fix this and will have to re-live those sins. Which is why he starts again in the end where the movie originally started. It's not abrupt, it doesn't need a heroic badass ending, it's not a cash grab for a sequel. If you want 10 mins more of the true "ending" re-watch the first 10 mins of the movie. the curse and events will keep on repeating forever.