Paranoia

An intense, irrational, and persistent feeling that others are trying to harm, deceive, persecute, or conspire against you usually in the absence of prominent hallucinations or marked thought disorder. Possible causes are mental health disorders (schizophrenia, bipolar, anxiety, PTSD, isolation/loneliness), substance abuse (cocaine, cannabis, amphetamines, alcohol abuse), neurological conditions (Alzheimer's disease, Parkinson's, dementia), sleep deprivation, chronic stress, or age-related sensory decline (worsening sight or hearing).