Hello Marco.
I wish I had some really profound advice, but never having been in your situation, I don't.
Please don't feel that this is your fault. How could it possibly be your fault? What, by being true to yourself and refusing to live a lie? By falling in love with a wonderful woman?
Divorce hurts. It hurts no matter the circumstances. It's easy for children to place the blame on the "other man" or the "other woman" rather than their parents. No matter what they may say, your wife's kids are hurt and angry about the divorce, not about you.
If her children talk about you, it's because they require a scapegoat, just as I found ridiculous reasons to pick apart my new stepmother (she's weird, she wears a wig, she locks herself in her room and gets off on vampire films).
During the divorce, I was so angry with my mother, that I moved in with my father. She wasn't seeing anybody at the time, so I doubt your wife's kids' actions have anything to do with you.
The divorce is just a major change in their lives, and it'd be the same even if your wife were single.
When the divorce is over and the din dies down, her kids will come around, just as I did. Nothing can break the bond between a mother and her children.
As Melissa and Chynna said, the last thing your wife needs right now is to lose you as well.
On a lighter note: Great pic! It would seem that you get better looking with every new photo.
Nero