Once that story takes hold, the triggers multiply. The way they chew. The way they leave their towel on the floor. The way they breathe when sleeping. Hate, in a shared room, is not a loud explosion. It is a low-frequency hum that never turns off. Studies on social pain show that chronic interpersonal conflict in a confined space raises cortisol levels similarly to physical threat. Sleep quality deteriorates. Hypervigilance sets in—you listen for their movements, anticipating the next annoyance. Your room, which should be a sanctuary, becomes a battlefield. Some people develop symptoms akin to mild PTSD: racing heart when hearing their footsteps, intrusive thoughts, avoidance behaviors like hiding in the bathroom for hours.