[wayner]

I think Facebook makes people think they know others better than they do, and it tends to blur the lines of appropriateness for some people

As a nice guy I rate his actions as inappropriate at best

As a pessimistic guy I rate his actions as aggressive or malicious

I don't think you overreacted
(You wouldn't want to have seen my reaction if it was me in your shoes right now )

At a minimum I wouldn't have simply unfriended him, I would have confronted him and called him on it, for a start