i'm a bit surprised at the people saying you dont have to pay her anything - if you came into my house and broke something, accident or not, i would expect you to pay to put it right!
It being an accident doesn't mean you have no responsibilty, you cant just shrug and say 'oops'
why should i lose my possession and lose the money it cost me because of your accidents?
'but for your actions' i would still have my item intact - so it is your fault.
just because its a decorative item and therefore she doesnt 'have' to buy a new one, is irrelevant - what if it was a necessary item you had broken? - like her kettle or TV, or couch - something she will need to replace? why should it cost her twice? she's already paid once.
Accidents dont mean you get away scot free, they just mean you didnt intend to cause damage - you are still responsible.
try saying 'oops it was an accident' if you break something in a shop, or damage someone elses car in a crash etc - the court wont just say ' aw well he didnt mean to, lets just let him off eh?' - they will make you pay for the damages.
also the people saying shes not a real friend for expecting you to pay - well i'd say the same thing back - what kind of friend goes into someone elses home, breaks something then just expects not to pay, simply because they don't want to? what kind of friend does that make you? you should 'want' to put things right for your friend!