What happened here?

I ran into this guy again a couple of weeks ago at the same place where we had met and chatted several months ago. We never dated or anything, but it seemed that there was something brewing. When I saw him a couple of weeks ago, within about 30 seconds he told me he had a girlfriend, fist punched me, and told me she was there. I was breezy about it and asked him if he was in love with a smile (like a pal). He said he wasn't; it was too soon. I never saw the girl - oddly enough.

Even odder is that almost every weekday since then, we have run into each other at this place around the same time. Now it's almost expected, although neither of us mentions seeing each other the next day or anything. When I ran into him the first time after the girlfriend proclamation, I was pleasant and aloof and left first. From then on, he has been very attentive and conversational and even gave me a kiss on the cheek one day before leaving. One day, he wore eyeglasses for the first time I had seen, and I commented that I liked them the next day. He told me they had no optical value; they were just for fun. (He wore the glasses again the next day.) The other day he told me that I always looked so nice with a big smile. I thanked him, and I explained that I was going to work. He replied with a smile and "Is that why?" (strange question) I left before he did that day, but he caught up to me in the parking lot, and we chatted a bit before going our separate ways.

Unfortunately, and strangely, the last two times I have run into him, I feel like I have been blatantly ignored. One time he came up to the area, took a seat and said nothing. Several minutes passed before I glanced over and simply said, "Good morning." He didn't even look over but uttered the same. When he walked away, I had turned to see where he was going, and he smiled and waved. The next day, he was standing when I approached the area, and he looked at me coming, then turned away for a second, then turned back to me. I simply walked behind him on my way to my seat and quickly said, "Good morning." He gave me a quick repeat of what I said and took off like his butt was on fire. End of story. What in the world happened??? (Incidentally, no mention of the "girlfriend" has been made since the encounter a couple of weeks ago when he seemingly couldn't wait to tell me that. It wasn't warranted, as I never really let him know I was ever interested and/or available. His behavior since then has not really jibed with this supposed girlfriend of his.