To busy to write more but must say this is the most understandable comment I have read from you for some time. Please take this in the spirit it was given, a compliment, and to wish you all the best for what is shortly to be the festive season.
If you used the term "sublet" correctly, it means she is renting the place from a tenant who holds the actual lease. That in turns means that pursuing this could get her evicted.