Most Helpful Guy
Not sure why it bothers you so much. Us people are confusing beings. by the way, he may have just set up a profile to look at pics (you were looking at pics too) or maybe he's looking for someone new (sounds like you weren't). Either way, that is basically his business and his life to lead. I know that doesn't make it any easier for you. I'd just try to direct your thoughts and energies somewhere more positive. Some don't deal well with being single and unattached at all (not always a good thing) and others may do better in the long run by taking time to ask self questions about what is really important in a bf/gf. Hold out for the right one.
Most Helpful Girl
Most guys do this even before they break up, because they are planning to, but want to see what's out there before they do. It's pretty low but just be thankful you aren't with the jerk anymore. Don't contact him over it because you'll come off looking petty and stalkerish.