I'm posting here because I'm rapidly reaching the end of my tether with a colleague at work. Hope you're sitting comfortably because here I go

I've been working in this company for nearly a year now. Upon my entering the company, I immediately hit it off with this girl, who initially seemed very charming and beguiling, only to end up repeatedly becoming the victim of her abuse.
I am female and bisexual, and she's apparently bisexual too (either that or she's just very good at feigning...and actually I wouldn't put it past her), and I'll admit I was attracted to her from the outset and she and I have had repeated flings without actually dating. The not dating thing is due to her rather than myself. Since sitting down and evaluating my relationship with this colleague, I've come to realise that I in fact suffer from a personality disorder myself (the dependent one), and I always feel that I need to be with someone in order to feel comfortable within myself, and that I must do whatever is necessary and humanly possible to keep other people happy. With hindsight, I can see that my colleague saw this in me and honed in on me specifically for that reason. She needed someone to abuse, and I was an easy target. Perhaps I should thank her for it, because at least now perhaps I can seek help for my disorder.
Initially everything was fantastic, and it seemed that this colleague and I had everything in common. She really is a master manipulator, almost to a sociopathic level, making me believe that she and I had a special bond that went deeper than the relationships of most other people. She kept me hanging on, stringing me along with false promises that we would date properly "when she was ready", and getting me to do things for her in the eventual hope that I would eventually satisfy her enough to make myself worthy of being her full time girlfriend. Then she began going through periods of ignoring me for seemingly no reason, later telling me that I'd upset her in some way. I'd always be the one to apologise, and we'd kiss and make up and everything would be fantastic for a little while, after which the game would begin again.
The ludicrous thing is, I wasn't even labouring under false pretences. In my heart of hearts I knew our 'attachment' was all too good to be true, and even that she was manipulating me in numerous ways for her own ends. I was conscious and aware of all of this. However, as usual, the dependent in me - desperate for love and affection despite the pitfalls and consequences - deliberately overrode all the warning signs, because I would rather be with someone who abused, manipulated and humiliated me, than be alone. So, in order to try and pass this girl's tests and eventually 'win' her, despite knowing that it was invariably a losing game, I let her manipulate me. We work in the same office, and a very small one at that, and whenever something went wrong that was her fault, I would voluntarily take the blame for it to please her. When she was tired, I'd offer to do her chores for her. If overtime was needed, I would volunteer myself for it just so that she could hug me so sweetly and whisper sweet nothings in my ear. I knew she was doing this to me, and I did nothing.
As of now, I am on the end of a fortnight-long ignoring game by this colleague. I've had to come into work every day and be subject to her shunning me completely, yet interacting jovially with our other workmates. And, to be honest, I don't know if I can cope with it any longer. It hurts, in too many ways. It hurts because I know I deliberately let myself be manipulated. It hurts because part of me still 'loves' her yet knows she has never, and will never, feel the same. It hurts because it's affecting my productivity and output in my job, and my boss had 'words' with me a few days ago saying that perhaps I should reconsider my position at work.
What I do know is that I cannot continue without saying anything, however, it seems I'm damned if I do and damned if I don't. I want to assert myself and confront her, but I've read this isn't the best course of action with HPD's. If I did do that, she would find some way to make my work life even worse than it already is, or get me sacked, or both. But if I resigned, she would have won. And I'm highly reluctant to talk to my boss, because she's one of these 'tough' people who sees issues as weaknesses, and the most likely thing she would say to me would probably be that I was in the wrong job.
I hope someone here can advise me on what to do, because this is driving me up the wall.
Thanks.