Second Chances... A Go or No?

What is it with giving people a second chance? I am one of these people that it is pretty easy to let it slide off my back and keep moving... but when it comes to feelings and getting to know someone, I am a little more sensitive.  
Here's the scenario... I stopped talking or whatever the new term is these days, to this guy over a year ago because I felt I was being treated like I was unworthy of his time... well a year later, he begins texting me again, really? Yes really! So I simply asked what happened to his other lady friend and that I was not going to be a fall -back girl, because that's not how I roll. Let me explain, during this year,  I had really taken time to focus on my relationship with God and working on my masters, So I had changed quite a bit. When he started texting me, I made it clear I wasn't sure, but I continued to talk to him. Let's jump to present time... After me thinking all those "what if" questions of what if I don't give him a chance, what if I am just being closed off and him blowing me up pretty much every day, I saw things as different, even though I still proceed with caution. 
So it took every bone in my body this time to even think about having dinner with this person and when I did everything was going great and it dawned on me, "I might actually really like him!" But before I could even give that a full thought, he starts acting strange. As soon as our night was over, which I even stepped out of my comfort zone to go to a restaurant I wouldn't go to on my own, my thoughts started running a mile a minute. I know I have a problem with over thinking things, so I am really trying to be positive... however I haven't even talked to this guy since our dinner, well once and that's because I text him! What the heck! I just don't get it. 
Why do men want everything on their terms, even if there are no expectations... I just wanted to get to know someone, is that too hard to ask? So I guess I have to go back to being unavailable, but I will not get hurt again by the same person.. the first time is shame on you and the second time is shame on me and if it even is given a third.. then I am crazy!