I Like the Third Option

Here's the deal.
I love this girl. I've loved her since I got to know her, I've had a thing for her since I met her.
The last two months have been horrible, and yet, things were starting to get better.
we had nice conversations. We spent time together and enjoyed each other's presence. We weren't around each other 24/7, dragging each other down because of what was going on in our lives. We started working our full hours again, we started living our lives again.
Yet, the lingering doubts never washed away, they only got pushed to the background by the things I enjoy doing on a regular basis, and she was sleeping around on me. She was using me for alcohol, and every night we spent together going back to her ex-boyfriends house to get laid.
Thursday night we had a great time at Lynagh's. We had great conversations, and then we came back to my place, and I confronted her on some issues that had come to the forefront over the last few days.
She ran away. She decided not to deal with my confrontation, she decided that it would be better to be elsewhere, and pretend the conversation never happened.
I called her out on her behavior toward her ex and me.
I told her, that though I may be wrong, I'm going to tell you how I percieve things, and then you can tell me how I'm wrong.
I said I think she wants to be with me, but she's keeping the door open with her ex boyfriend. Then she started acting weird, and I asked her what was going through her head, and she said she was plotting her escape.
I must have hit the nail on the fucking head, because when that came out of my mouth, she reacted immediately.

I then took her home, and she kicked me out very quickly. She kissed me on the cheek, and I asked her if that meant we were over, and she said no, and leaned in and stuck her tongue down my throat.
Promptly thereafter she shut the door and locked it.
Part of what pissed me off was that at lynagh's she told me she had thirty dollars, and then I spent money on her, she went and bought cigarettes and a 12 pack, shared one beer with me and left.
I asked her if she was buying beer to drink with other people, and she said 'no, I want to have it, but i won't drink it unless you're with me..." but the phrase was weak, and it lacked conviction.
I don't know what's going on... and that's another reason why I got so angry last night.
I don't remember what I said to her over the phone, but I remember leaving three voicemails, the last of which was something along the lines of "at this point in my life i need a girl that cares about me more than herself, and I care about her more than myself, and so it balances out and shit still gets done... then a long pause, and a muttered 'it's over.'

Since telling her, at least on voicemail, that it was over, I've had a lighter load on my shoulders, but then again, I start to think that things were getting so much better, and that this weekend was going to be great.

The worst possible outcome of the immediate future is getting back with her, remembering everything, knowing nothing and heaped under a boatload of stress about what I want to know, and being a fool for a girl who is only using me.
The best would be knowing the truth, forgiving her, wiping the slate clean, starting over at a later time when she's past these foolish actions, trusting her, enjoying my life and those who are in it, and every moment we spend together.
Either of these outcomes can come to pass, and then there's the third option;
Just stay the hell away from her all together.

I like the third option... I put up with too much stress, too much abuse, too much betrayal, and too many actions that should have made me slap the shit out of her and kick her belligerent ass to the street to find her own way home, covered in her own urine and so drunk she can't talk.
I'll be her friend, but I'll be damned if I do anything for her...
And I'll enjoy my time with Angela.