Is It Just Me?

I tend to be pretty confident about who I am as a person. Some people seem to like me, but I am reasonable enough to realize that there are many others that do not. Although I like being a likable guy, it doesn't bother me that some people do not like me. In fact, I believe that this is an unavoidable part of life.

However, recently I've had a number of people that appeared to ostentatiously dislike or ignore me. then later, the same people would show interest in me. I don't get it.

Example: A few weeks ago the BF and I went over a friend's house and met a group of guys. One of them seemed to really click in a social way with the BF. A few times throughout the day I tried to engage him in conversation, but it was obvious that he had no interest in speaking with me. He wasn't rude, just not interested. We saw him for the second time a couple of weeks later. He greeted the BF with a big, endearing hug and greeted me with the absolute minimal acknowledgment allowed by custom. So I was very surprised when later during "play-time" he silently approached me and started fondling me. I was so confused that I didn't know what to think.

I have other, similar recent examples, but I think you get the idea. I'm wondering if perhaps I am transmitting something that makes me seem unapproachable or is this just natural behavior on their part.