Bublin, my heart goes out to you. I have been in a relationship with a psychopath, and it's really tough loving people who have personality disorders. They're usually in denial and like Thick Hair said, their crazy will make you crazy. I'm totally co-signing with Ballerina - the only remedy is no contact. These types do not change because they do not believe they have a problem. A good friend of mine is waking up to the antics of a crazy dude with AsPD and I think she's finally understanding that this is like a sickness that goes untreated. You can't love, sex, feed, or hope it out of them - you just have to leave them and completely ignore them popping up months and years later with their apologies, sob stories, and manipulation. They will promise you the world and walk a straight line until they think they have you and then the cycle starts all over. It's maddening because if you're a person with half a conscience, you try to accept responsibility for whatever you do they may provoke it until you realize that they're just crazy and no normal, sane human being would have an emotional hair trigger or be that insensitive. My words to my friend were, "Leave now. Tie up your loose ends. Never speak to him again. Ever." There is no reasoning with these types.
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There's a lot of good information there for getting your head on straight after dealing with these crazies. One night several weeks after I left crazy dude, I stumbled on that and was floored that people were describing my experiences to the letter and that I wasn't alone. I had never felt so much peace and clarity about it all. I subsconsciously knew he was a self-destructive jerk who was going to hit rock bottom from all the lying, manipulation, promiscuity, compulsive behavior, etc, but to actually see the symptoms was somehow freeing for me.
Part of the relief is realizing that there's a name for their brand of crazy and realizing that it's not you. Beyond that though, I think you have to take full responsibility for your role in engaging the crazy and be willing to become like sand to their efforts to bounce their tests and mind games off of you. Eventually they get tired and move on to their next victim who they can leech dry of sanity and anything else they want.
I used all kinds of methods for extricating myself mentally & emotionally - I made a list of the outrageous nonsense and posted it on the wall so whenever the urge to call popped up, I referred to the list and found something more constructive to do. Having that list handy quickly dissipated what psychs call "malignant optimism" and idealizing the past. I wrote like my life depended on it, and fortunately, I had very supportive people in my corner so I was able to talk it out as often as necessary and they confirmed that he was off in the head - not in a sarcastic way - but in a serious, "I'm concerned, he needs an intervention" type way. The lying was other worldly.
I definitely agree with the ladies that there is life after these kinds of people so don't give up on humanity although you want to because it's overwhelming to imagine somebody being that selfish and cruel. There IS life after this, and there's a valuable lesson for you as well.
Every other relationship I had improved 10 fold after that one ended because I had more clarity about what a healthy relationship looks like and I was in a new space of emotionally investing in the right relationships. It also fine tuned my intuition and avoided some losers who exhibited the same tendencies.
You'll survive and you'll be so much better for it. Hang in there!