Why do people have to hurt each other?

The other day, I received an email from an acquaintance who I knew must have been having marital issues for some months and noticed that her last name was now displaying as her maiden name. While we are not what I would call friends, she seems nice enough, and I felt sad for her at that moment. So I sent her a note to express my condolences, making it clear she didn't need to respond. I had no idea what had gone on between her and her ex.

Well, she responded with what seemed to be genuine gratitude for my acknowledgment of her situation, and from what she said I am under the impression that he really hurt her. I don't know what exactly he did, but what doesn't really matter.

Why the hell do people do that to each other? I don't mean divorce. I mean turning on the person they promised to love forever. If you don't love her any more, fine. Have a frank discussion and leave. A heart would be broken, but at least you're not "twisting the knife," so to speak. Lying, cheating, emotional or physical abuse (I'm talking generally now, not about her specific situation, as I don't know any details). Why? Isn't it easier to just leave? Or not get married in the first place? Maybe make sure you really can live with the person before getting married?

When one partner is actually in love and the other starts with the deceit or abuse, she or he can be blind to any clues that a problem exists. Then when it smacks them in the face, they are devastated. Add in on top of that the stress of going through divorce proceedings, and it can really affect a person for the rest of her life.

Why are people so mean? Why do they cut so deeply the person they chose as a mate? How can you go from loving someone enough to share your life with them to intentionally inflicting pain? Even if you don't marry out of love - if it's lust or finances or you just want some company - why be a jackass? Do people take pleasure in that kind of thing?? Does it make them feel big to totally crush the person who chose to settle down with them, put up with them, and have children with them?

I just don't get it. Yes, there are times I want to make someone "pay" in retaliation for some wrong (actual or perceived), but it always makes me feel crappy afterward, and I end up apologizing, even if it falls on deaf ears. I have the urge to at least punch the guy in the nose who caused my acquaintance so much pain and I feel he deserves it, but it wouldn't undo what he did. I also have no idea what she may have done to him.

Now that I ranted about that, I can beat myself up a little bit. At the beginning of the post, I mentioned I knew she was having marital troubles. Yet I never once reached out to her before she sent that email. My philosophy was that she would tell me whatever she wanted me to know. But is that philosophy flawed? I actually feel kind of guilty. I know what it feels like to trudge through the day without revealing my troubles while secretly but desperately wanting understanding or support from someone, anyone, even everyone. She didn't have to tell me anything for me to tell her she had my support. It's too late to go back now. It's also too late for me to be up - it's way past my bedtime and I'm sleepy. Good-bye for now.