My 14-month-old lab was fully potty trained for months but now she's peeing in the house again, usually when I'm in another room. I'm losing my mind. Why is thi

Three common causes: medical issue, access without supervision, or incomplete training that looked complete. Rule out the first with a vet visit — UTIs are common and fixable. If she's healthy, the problem is management. She learned to hold it when you're watching but never generalized that to 'hold it always.' Go back to the protocol that worked the first time: scheduled potty breaks every 2-3 hours, tether her to you with a leash when she's inside so she can't sneak off, and heavily reward outdoor pees. If you can't supervise her, she goes in her crate or a gated area with no carpet. No free roaming until she's gone 14 days without an accident. Most regressions resolve in 2-3 weeks if you remove the opportunity to rehearse the mistake. If she's peeing in front of you or in her crate, that's a different problem — either medical or severe anxiety. See the vet.