break the door? it seem just old wooden door, it can't be that difficult to break it with home items, same goes for windows, she had hours to do it while he was in school teaching, don't tell me you can't break glass or wooden door within hours. heck she could try break the floor, these old buildings don't have concrete floors and then escape through apartment below

also why not throw boiling water in his face?

i thought about setting apartment on fire but that would be too dangerous for her and it could go unnoticed anyway when nobody noticed burning container

btw. there is plothole - her phone has no SIM, but you can still call emergency services even without SIM, heck you can usually call them even when there are no bars, since these calls have maximum priority and can work with lower signal

she could also learn to lockpick, had all the time in world and it seem he used ordinary keys for both locks