Did I overreact or was what he did enough to be a dealbreaker?

[Little Me]

All the people mentioned in the story below is about 20 years old.

I recently dated this guy (until the other day). Lets call him Jack. We talked about exes and I told him that one of mine is still one of my best friends, and that he's a great person. Lets call him Harry. Harry is a lot shorter than I am and very overweight. Jack is sort of good looking. Jack and I know many of the same people, and someone had shown him Harry's Facebook profile the other day. A common friend of ours told me about it and told me that Jack had said that he thought Harry was so ugly that he was embarrassed on my behalf. Jack had actually been embarrassed that he was dating me since his friends know Harry and was making fun of him. I brought it up with him and he didn't have much to say so I called it off. I don't like it when someone disrespects my best friends or me. I still like and miss Jack although I think he's an idiot.

Did I overreact or was what he did enough to be a dealbreaker?