Mistakes made,lessons not quite learned...

I dated a girl for less than a month in 2006 and she got pregnant. In panic i married her and as i was raised by mom i didn't want the child to grow up without a father. This girl was also 3 yrs older than me. We argued almost everyday even and at one time we had a fight after the baby was born and it got physical. This was the first time it had ever happened in a relationship of mine. Prior to this fight we had been sleeping in seperate bedrooms for 6 months and had been married for just over a year. During the course of this marriage i had told her i wanted out and we should split. It was really getting nasty. I felt emasculated as she was disrespectful most of the time. I guess as revenge i started having affairs. In October 2007 i had an affair with a married woman. She left for the USA to join her husband in December of the same year. I got divorced in 2008. She told me she was pregnant over the phone. The baby was born 10 months after our last encounter. She said it was mine. I had confessed everything to the woman i was married to. Lets call her A and the affair B. B said she didn't love her husband anymore and that she wanted to be with and loved me. She'd call me while he was downstairs for example. When she was here in Nigeria we once had intercourse while her sister-in-law was in the adjacent room. She said she found it exciting. Not to digress, her husband found out about her affairs. I wasn't the first she had had but he got particularly irked by me because of the love child. I had suggested abortion to A and she said she'd let me know. She went quiet. She didn't even tell me she had given birth. I found out only after i had called her sister 10 months later. A's husband caught wind of the situation. Naturally he lost it. He got violent towards her and they later broke up. I'd always make sure i communicate with her during her trying times. She was now staying with her other sister in law. She told me she wanted to go to a Snoop Dogg show. I told her it was improper given the situation she was in. She was staying with her two kids at her sister-in-law's. She shouted at me then went offline. I later found out she went to the show anyway. She enrolled for school, moved out and got her own place. She got grant money and didn't hear from her. This happened in the last quarter of last year. Again i looked for her in December. We had previously shared email passwords and she had changed hers. We picked off again this year. The problem is we're talking about marriage and a lot remains a mistery. She claims the child she gave birth to is mine yet we had to fight for me to get a single photo of him. The child bears her ex-husband's surname even though she took a new birth certificate for him this year after misplacing the original. She won't let me talk to him over the phone. When we talk over the net she quickly gets upset and goes offline. It seems when things are going well for her she forgets about me. When things turn upside down she starts texting me saying she misses me. I run back to her and the cycle repeats. She loses her mind when i mention her ex. She told me she never loved him and they never got along in the States. I ran into photos that showed them having a good time in America and she lost it. I don't understand what goes through her mind. I know we sinned before God with what we did but i was trying to remedy the situation hoping good will come out of it. I really love her and would love to marry her but is this the wisest choice? I'm so afraid of losing that i succumb to her will and i feel the success of our relationship is based on the amount of effort i put in. I'm so confused right now. One minute she tells me it's not working, i beg her then i try to fix this. I want to make the right decision for once in my life. I don't want to regret again. What should i do?