My take is she has told you she would still like to be single without coming out honestly and saying it. She wants her freedom still, and that's why she's not committing sexually to you. You could confront her about the social media posts, her hearts to other guys and her sexy picture, but she'll likely deny it. I would just tell her you're not ready for a relationship, so I think we need to part ways. Save yourself all the heartache and trouble.