Getiing married but in love with someone else, or the idea of it?

I am getting married in seven days, we have been together for 4.5 years, lived together for almost four years and have been raising my daughter together. He is a great dad and role model to my daughter, and she believes this is her dad, he is all that she knows. He is a great supporter of our family and loves me and has never, nor will ever cheat on me. However, I have cheated on him, most notably a few weeks ago, where I met this guy and we stayed together the whole night, then we met up again the next weekend and stayed at a hotel before he left for Iraq. I felt an immediate connection to him, as did he with me, and we talked for many hours, getting to know one another, talking about our lives, thoughts, beliefs, etc..also was great. My fiance and I have been fighting non-stop leading up to this wedding, about money, how to discipline, he has been yelling at me constantly, also we have not had for almost a month! I am just not attratced to him anymore..It is sad, I am now unsure about our future, I feel like we will most likely divorce within a few years, if not sooner. I have been talking with the other guy almost daily online. Anyway, I really am infatuated with this guy I just met, which I know is dumb.. I barely know him.. but now I feel so un in love with my fiance, and I seriously would call off the wedding if people had not already booked flights and have paid for everything, I would. And I told my fiance I would call this off if I could too while he was going ballistic on me yesterday... But here we are, going forth.. wtf, what do you think?