buyer is backing out of contract because they changed their mind

[Scott Lepore]

My buyer has backed out of contract because she wanted to expand basement (she did not mention this in contract) and it is going to cost more than she thought.  She wanted to demo basement wall, dig out 500 sf of crawl space and put egress where concrete patio it.  Did she think this would be cheap?  The agent marked the inspection box as the reason for backing out but this was not an inspection and inspection had not been done yet.  n my mind and inspection is for finding any current or potential problems with the house.  Given the generous buyers rights when it comes to getting earnest money back I'm wondering if I stand a chance of keeping earnest money.  It just doesn't seem right that she can get it back after I passed on other offers and she never said it was contingent on cost of remodel.  Any input is greatly appreciated.  Thanks in advance!