Well, I care if he broke her heart by being dishonest with her. That's a shame. But you're right; those kind of situations happen to millions--just not on TV/media/Internet.
But like you, I didn't take out revenge. Believe me, there are many who would have, but I think that type of reaction causes more pain and repercussions at the soul and psyche levels. IMO, being judgmental and vengeful is like drinking poison. There's that wise saying "it's not what happens to you, but what you do with it". And another wise saying is "the best revenge is living well". IMO that's what Melissa has been doing ever since the Jason-Molly fiasco. As far as I know, she put it behind her, moved on, and didn't lash out in the media. And look at her now.
I'm not criticizing Tanya (after all, I haven't even heard her whole story about it yet and may never), and I'm not defending Jake either. I've never been a Jake fan anyway.