In PANS/PANDAS, sudden onset of irrational anxiety
, esp. separation anxiety
, OCD, (including needing to confess), anorexia, and frequent urination (even new bedwetting), and behavior regression are common symptoms. The cause is an antibody attack on the brain, not anything anyone did - not her, not you, not classmates or anyone. If it is this, then anti-anxiety meds, prayer, meditation, sleep, won't take care of it; needs medical treatment for whatever underlying infection.