Don't know what to do with this girl

I'm currently in a bit of predicament. This has truly been the toughest year of my life. I started seeing a girl at the start of this year who I had been friends with on FB for about 4 years. She had been overseas during this time and had moved home just before the end of last year. I had always been quite keen on her and the first time I met her (four years ago) we actually hooked up and basically had sex (I was too drunk and we were making too much noise in a squeaky bed next door to our friends room). I was aware she was back in the country but decided not to contact her because I had a feeling that something might happen and by that stage I had decided that I wanted to travel overseas and I didn't want to start anything. Also, from previous relationships I knew that I had the ability to really hurt girls (not purposefully) and let them down and I was hesitant to get into a relationship again.

Anyway, we both ended up at the same party on New Years Eve and sure enough we hooked up again. It was amazing, and from then on we were full on. She would stay 3 or 4 nights a week, she introduced me to her family and her friends. It was the most amazing honeymoon period I have ever experienced. I was loving having her around and had decided that I didn't want to go overseas anymore and could see myself starting a family with this girl. That is what she wanted and she had mentioned kids a couple of times and I had said that I was open to the idea.

So 3 months pass, I started noticing a couple of things I didn't like about her, and all of a sudden I get this feeling that I am going to hurt someone again. I take a step back and start thinking about what I am doing, whether I still want to go overseas (which I thought I did) and whether I really want to have kids (which I couldn't honestly say I did). During this time I had no feelings towards her, which I couldn't understand because I was so in love with her. These thoughts kept me up a couple of nights and I couldn't eat so I decided I had to tell her how I was feeling. She came over and I broke done crying when she turned up. We sat down and I told her that I had been thinking about moving overseas and I didn't know whether I really wanted kids. She was really good about everything and said she wanted to stay together, and if we have kids we have kids and if not that's fine too, she said if I decided I did want to go overseas that was fine too but she wanted to fight for me. I felt a lot better after I told her what I was thinking and I relaxed, my feelings towards her returned and things went on as normal for a while. Little did I know that this was the beginning of something really bad.

For a few weeks things went on as normal but she slowly started to withdraw. I asked her about it and she said that everything was fine and she was missing me a lot and thinking about me all the time as I was her. But she withdrew more and more till it got to the point were I felt like I was going crazy. At one point she saw me once in 10 days. I felt like I had ruined my life and my chances with this girl and had made the biggest mistake of my life by telling her what I was thinking. I still wish that I had of given it more time before I opened up. By this point the whole dynamic had changed and I didn't know what to do. I asked what was going on but she would never give me anything and would say she still wanted to be with me.

So about a month into this I went on an overseas trip, right in the middle of this big issue we were having. Bad timing. I had a lot of time to think about things and I was just not feeling like myself. I wasn't happy at all and I couldn't go on like this for any longer. After I got back I gave it about 2 weeks then had her over and said I thought we should end things. Again, she was really good about i, said she still wanted to be friends and that she still wanted to be in my life which I wanted too. We then had dinner together and had sex.

Since then we have stayed in touch and she will visit or I will visit about once a week, we still have sex and I still really like her. We are planning to go on a trip together in 2 months and we are both really looking forward to it.

My problem is I don't know what to do!!! She'll be completely distant one moment and then full on the next. I won't hear from her for a couple of days and then she'll be texting me all day. The other night for example she came over for dinner and was really distant for a couple of hours and then went off to have a shower then came back and jumped on me and we had the most incredible sex I think we have ever had. Then the next day, nothing.

What do I do!!! Do I marry this girl? Do I get her pregnant? Do I drop it and go overseas? Does she still want to be with me? Do I give it another chance? I do feel I really love this girl and I can't see any easy way out of this. Any thoughts?