If your cat, who you've had for a long time, suddenly starts hiding, it could be due to a few reasons. One possibility is that it witnessed something frightening in the house, causing psychological distress and leading it to hide for self-protection. Another reason could be that your cat is simply playing a game, hiding in a dark place to ambush you when you least expect it. Finally, your cat may be hiding because it's not feeling well and doesn't want to be seen or touched. Pay close attention to your cat's behavior; if you suspect a health issue, it's important to take your cat to the vet for a check-up.

Reasons Why Your Cat Might Suddenly Hide
1. After having lived with you for a long time, a cat should be accustomed to its environment and have a bond with you, so suddenly hiding is unusual behavior. In this case, it's likely that your cat saw something that terrified it, leaving a psychological scar and causing it to hide out of fear. The psychological impact can be a significant reason for cats to retreat into hiding.
2. Your cat might be playing a game of hide-and-seek with you. Cats have a natural instinct to avoid predators and enjoy hiding in dark places, watching you try to find them. They might be waiting for the right moment to pounce. Also, if you've been neglecting your cat lately, it might be trying to get your attention and encourage you to play with it. This is a common behavioral cue that they want to interact with their humans.
3. A cat's personality can change, but they are often naturally timid. They might lack security and hide during the day, only coming out when their owner comes home. If your cat has started hiding from you too, try to remember if you've done something that might have made it distrust you. This change in behavior is worth investigating, as it could indicate that the bond needs some mending.
4. A sudden change in your cat's hiding behavior might be an indication of illness. They tend to hide when they are sick and want to be left alone. You should pay attention to your cat's health. If you see anything unusual, take your cat to the vet for a check-up. This is especially important because cats often conceal their discomfort, so hiding could be the only visible sign.