Yes, I agree with you. It was wrong. H3rmit was right, sometimes you get to a point where you can laugh or make light of the terrible things in your past, but that doesn't mean that others are at the same point in their lives. They should not have posted that publicly.
VMblue makes a very good point as well. It does send out the message that it IS ok. It is NOT ok...It is not something to be made light of.

I'm so sorry that someone close to you hurt you that way. Even though they didn't know, they should have respected you when you stood up about the post. ((hugs)) The others who posted are right, maybe you should block at least her post from now on...if she does have that kind of humor, or is to the point where she can laugh about it, you don't want to be triggered by another post like that, if she makes another one.