My girlfriend doesn't want me to talk to another woman anymore, what to do?

To explain my situation briefly. I broke up with my fiance of 3 years due to ongoing problems in our relationship. Basically this: a href="http://www.allaboutlifechallenges.org/cycle-of-abuse-faq.htm" rel="nofollow"http://www.allaboutlifechallenges.org/cy…/a over and over again. Things have even been bad with her in front of my family and before she left I told her, not asked her that things had to be different from now on. Long story short, when I was busy working one day with a script she asked for help with hers and again, I was busy so told her I didn't have time to review her entire script and can possibly do so later. As a result she informed a good friend of ours when he showed up, complaining to him about it. Then she leaves, running off with him, ignoring my calls. Now if it were anyone else I'd ume she was cheating, but this guy is also my friend so in all fairness instead of talking to me about this she made him a messenger relaying our problems through him. Where right there I just decide to break up, that I was sick of these problems. And whats about to entail made me never regret it. I call her later out of spite where she finally answers me telling me she is going to her ex boyfriends house tomorrow, and regardless of our problems and my still having feelings for her I protested, whereas the next day she went to see him anyways. In the meantime I met someone very similar to myself, whom we have a lot in common with, who was interested in hearing about our relationship, I told her my problems , and the way she ysed them is the exact way I have.....Its like she spoke from my subconscious. I never braved to sit down and talk with my girlfriend about the problems as she would often be stubborn and just rush through them to find resolve, where the same things would happen again. And I don't consider this other woman a rebound...Anyways.....That is the introduction of her...Meanwhile my ex claims to be at her ex boyfriends house. Where they were both laughing at me when I actually told her she was making me miserable. I suppose if she wants to jump on her ex-boyfriend a day after our relationship thats up to her, I just don't see why her emotionally abusing me further was necessary. It came to the point where she finally joked "I'll get dressed then I'm going home."...I let that sink in for a moment quietly where she quietly whispered "I'm joking." then laughed at me again. Shortly after I hang up, and start pursuing things more with this other woman realizing I really enjoy talking with her. Later ex girlfriend catches onto this and tries to commit suicide, even ended up in the hospital. Afterwards she logged into my skype account stealing my conversation with this new girl when I told her earlier I would not allow it and she had no right to it. Regardless, after reading it she suddenly became all apologetic, telling me she will work on our problems and that out of all the times she promised this before "This was it", and that she "loves me". I forget what compelled me to make the decision to go back with her after her practically driving me to the point of insanity, she presented herself rather sincerely, I didn't know this other girl that well despite our mutual attraction and knew it was too early for a relationship, so I got back together with her on the grounds that I am not going to rid myself of this other girl just because we're back in a relationship. That I am going to be looking out for my best interests now, my happiness. However what I had with this new girl did not necessarily remain plutonic, (I did not cheat on my girlfriend) but in the way we acted around each other, this other girl eventually did things like text her saying "I'm slowdancing with your boyfriend." and later denies it to me despite my girlfriend provided a screenshot of it. Before the screenshot which was a last resort she just demand that I trust her and that it should be unconditional, needless to say I had to remind her of her past which evoked trust issues with her. So now after the other girl lying my girlfriend demands I stop seeing her. Currently my girlfriend has done that to me cause I didn't take action right away and find myself in a very difficult position. This new girl lied to my girlfriend, and to me about saying it and I did scold her for it, but right now the only person who wants me to stop is my girlfriend. Who hasn't been so noble in the past either, yet tells me I should forget the past and that she promised me...Etc...Etc....This was the last message I got from her "theres seriously something wrong with you. i will not stay with you while you continue to talk to her. if you want to be with her, then its over between us. and im dead serious". And I want to make myself clear, I asked a question on Yahoo Answers before about whether I should stay with my girlfriend, this was not the first time I was contemplating leaving her. During a visit at my house with my family it caused a lot of stress on everyone and there were mixed answers amongst yahoo answers s