It's quite rare for someone to actually be cursed, and it's much more likely to just be part of the normal flux of ups and downs people experience. If everyone is going through a rough time you may want to cleanse the house, which will dispel some of that negativity that's likely lingering around, and it might help people break out of bad moods, etc, which could be causing the "down" period to last longer than usual. There are quite a few different ways to cleanse a home, and there are several threads on the topic,
such as this one, that could help with cleansing ideas.