Why did this relation end this way?

I was introduced to someone about 4 months ago. This guy seemed to be into me and then his ex that he cheated on wanted to see if there was anything there so he told me that we weren't going to hang out. About 2 weeks later he came back around and said they didn't work out. So we hung out. One night at playing pool he was mad because I talked to a guy here or there. He seemed to like me. About 4 month's later we start talking finances, and he tells me he wants to add to this business he's started. He seemed to really motivate me to want to do better and to encourage him, I gave him the cash he needed to start what he needed. Now all of our talks have been strictly business. I work for a company that can provide a lot of potential business for what he does. I don't feel used necessarily, but I told him today that we did not need to be "personable" any longer. I told him we can be professional and that he did not have to pretend to like me for business purposes. I am not a stupid girl, I know where to take it from here. I just want to know how or why it would have to end this way when it didn't start this way. Is everyone more interested in money than the value of friendship or more, a relationship that could only lead to 10 times this one meager opportunity...?? Wow....(shaking head at self in disappointment)