AITJ for snapping at my MIL after she let my dad wander off?
me and my wife (35m and 33f) have my dad living with us. Hes 68 and has fairly early dementia, hes still got plenty of good days but he gets confused and he wanders, and a few months back he got out and we found him a mile away looking for a house he hasnt lived in since the 80s. So we never leave him on his own and the front door stays locked from the inside.
This morning i had a long client meeting i couldnt get out of and my wife was at a hospital appointment with our son, so we asked her mum to pop over for a couple of hours just to sit with dad and keep him company. She knows about the wandering, weve been through it more than once, and the one rule is you dont leave him unattended and you dont leave that door unlocked.
About forty minutes in dad sent me a confused little text that just said "where did everyone go," and my stomach dropped. I muted the call and rang the house and got no answer, rang again, nothing. Turns out my MIL had popped out to her car and then nipped to the shop on the corner for "literally five minutes" and left him sat in the front room with the door unlocked.
By the time i got home dad was thankfully still there, but the front door was wide open and he was halfway through putting his coat on to "go and meet your mother." When i asked her what she was thinking she was completely relaxed about it, said he was settled watching telly and shed only be gone a moment.
I told her she cannot leave him alone, thats the entire reason we asked her over, and the door being open is exactly how he ends up a mile away again. And she went, all breezy, "oh love, he was fine, hes not as bad as you all make out." I just looked at her and said you have no idea how fast he goes, and i need someone watching him not someone wandering off to the shop. She said i was being rude and that if i didnt appreciate her help she was leaving, so i told her i was perfectly capable of looking after my own dad and she was welcome to go. AITJ?