The first thing I think you need to understand is that this sort of behavior is common in Bipolar Disorder. You didn’t do anything wrong and her behavior is not a reflection of some deficiency in you. You may have very much loved her. The reality is feelings aside, is that you can’t love someone out of Bipolar Disorder, many have tried and found out as I did, to their disappointment and maybe even dismay is that it just can’t be done. Before they have a shot any “normal” kind of relationship they have to first accept that Bipolar Disorder is genuinely problematic. That takes a lot of courage as denial about the negative impacts of their condition is common. That said, the emotional bond was likely real, but she couldn’t sustain it. It's very likely that you aren’t the first guy she has treated this way and you won’t be the last. Remember, Bipolar Disorder is a life long condition, without some sort of commitment from her to addressing and managing it, all the hurtful push-pull, the cheating, the lies, the sucking you in just to turn around and reject you to playing up to you so hard while at the same time having a whole secret life of fun and excitement without you, and at the same time trying to get you to feel sorry for her while she was out concert hopping, or partying with everyone would have likely continued and for a long time, leaving you feeling seriously in the dumps, lonely and lovelorn. You could waste a lot years denying yourself love, pleasure, joy, happiness, and satiated fulfillment, longing for her. Read the story of the Greek Sirens it may help you understand and release your self from her spell. Also remember that Bipolar Persons suffer from heightened impulsivity, they are usually quite sexually charged, and flirtatious and if they’re good looking with a nice body watch out! They also tend to have drug and or alcohol dependency issues and a lot of shameful secret behaviors including sexual ones. So, as exciting as all that can seem, in the end you might be devastated, she would never be able to offer you, consistency, safety, reciprocity or even clarity. It’s tough though when you don’t really see all of this until AFTER they have wormed their way into your hearts to make the break. But nevertheless, you should still try not for her sake, but for yours, you deserve to have love, and thrills, but hopefully with someone who is able to TRULY and CONSISTENTLY fill your cup. Consider getting into deeper touch with yourself, doing so is not selfish but is critical to you living YOUR best life and if you find someone who can give you at least most of what you need, when that happens you just might very well look back on things and wonder what you ever saw in her I the first place.