Hi OP, Sorry to hear about your situation it's totally her and not you. I don't believe she cared about your tablet offer it sounds like she just said that to help her justify changing her mind and stuffing you round. She knows she did the wrong thing by leading you on/letting you think there was something there so I would say not to think of her in that way anymore because she'll do it to you again and again. It might be awkward to see her a lot but don't let her make you feel awkward she is the one who made it that way so put it on her and act normal but keep you guard up so you don't get hurt. Otherwise just take it as a life experience, don't dwell on it too much and keep your eyes open for a real connection.
Hope that was helpful.
Good Luck.