If you can prove that she had actual knowledge that that specific area was damaged then it would be very hard for a plaintiff to claim you had superior knowledge sufficient to allow a jury to find against you. That said, call your insurance company and let them get a free defense lawyer for you. Just because someone should not prevail does not mean you wont get sued.
Anyone can sue you, the question is whether they will win. If that is the only way for her to get in and out of her apartment, then she may have a claim even if she knew it was dangerous. However, if she knew it was dangerous and didn't have to travel out there, then she doesn't have a claim. Check your homeowners insurance. You may have medical payments coverage on it that would pay her medical bills. Medical payments coverage is paid regardless of fault.
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