It matters very little if she has a disorder. suffering from one does not excuse a person from making good choices like NOT sending strange men half naked pics. She's flaunting herself and with or without a disorder there is no excuse for that. Quit looking for a reason for her behavior and accept this as bad behavior period and that she's not acting like a girlfriend at all.

She's more upset that you snooped and clearly not as worried about the fact that you saw what you did, only that she got caught.