Expecting a child with her, but I'm in love with somebody else?

I'm only doing this because im having such a hard time making a decision. For the past ten years of my life, i've known and fell in love with this girl "Kerry". All through high school we were on and off...when we broke up one time, we each met somebody else and went off into relationships. Kery and I stopped talking when I went with "Amanda" and she went off with "Mark". We both went out with these people for nearly 3 years. She broke up with Mark in December of 2008, Amanda left me in Jan.of 09. We kept some of the same friends, so around April of 09 we met up at a party. It was almost like nothing has changed, we were both very happy, we started officially dating each other again that summer. We lasted til around Valentines day of this year. We couldn't find the time for each other in our schedules. She was in school and I was working two jobs. I was heartbroken and ran into Amanda one night who admitted how wrong she was to leave me, and how much she loves me. One thing turned into another and we had a one night stand.Amanda and I started seeing each other once in a while while Kerry and I didn't keep in touch really. Deep down I knew I missed Kerry, I wanted to just see her again and let her know how I felt and wanted to marry her. I went to break it off with Amanda for good, but before I had the chance Amanda told me she was pregnant and no matter what she wants to keep the baby. She started talking about how rough her life was growing up because her parents weren't together and she hopes we can stay together for good. I was in complete shock and couldn't tell her right than and there. A few weeks go by and Kerry called me with extra tickets to a baseball game, she told me how much she missed me, as well as I did the same. I didn't have the heart to tell her about the baby yet, I wanted to wait and see how things would pan out. I refuse to lead both of these girls on so I advoided Kerry a little bit until she calls up one night distraught about hearing the news about the baby. I have been being civil and trying to be the best man I can be to Amanda during this pregnancy. I agreed to go out to lunch with Kerry behind Amanda's back. Kerry and I shared the same feelings with each other, we want to stay together and get married. Of course, Kerry is upset about not being able to experience the gift of sharing our first child together, but she is willing to accept my future child. I'm so in love with Kerry, as she is with me. But Amanda is "in love" with me. I want to be there for my child, but Amanda probably won't let me she the baby if I stay with Kerry. I'm so beside myself. What should I do? I must also bring up that Amanda has moments where she loses her mind, I don't want to see her hurt my baby. She's crashed her car into my friend's girlfriend's car on purpose because Amanda felt she was flirting with me, which wasn't true (thats beside the point). Should I stay with Amanda and be unhappy? Or should I marry Kerry, and have a baby held over my head for the rest of my life. I can see Amanda being very strict and not let me even visit my child?