Is there a case for Hereditary Ratchetassness?

The saying is that an apple doesn't fall too far from the tree. I say it's not where the apple falls, it's where it ends up. Check it out:

A group of civilized Dallasites almost came to blows in John K's brand new spacious living room one night this week. I don't even know what channel it was on but there on the TV screen was some dude talking about the reason he cheated on his wife was because his father cheated on his mother. He said that's all he'd over known. The psychologist said that often children that see cheating, hitting, yelling, and general ratchetass behavior accepted as the norm growing up will perpetuate the same shadiness in their own grown up relationships.

Jayme went onto give the example that the abused tend to become abusers. Bryan said that he didn't believe that if your parents never taught you to be neat, you'll be a messy grown-up. Annette said that her mother was that needy woman who always clung to a man and couldn't make a decision without one. Her sister became the same kind of woman in relationships, Annette became the polar opposite.

I argued that at some point, if you are made aware of the fact that your behavior is unacceptable, it's up to you to break that genetic chain and evolve. I couldn't get past the thought that "my father did it, so I do too" seemed like a cop out to me. Someone brought up the Kennedys and the Marleys as glaring generational examples of sons who followed in their fathers' unfaithful footsteps. If someone tries to tell me that there's a DNA indicator that can predict infidelity, I want to know how to patent it... immediately

So we had several heated conversations going. 
1) Do men with cheating fathers cheat? (And is it a valid excuse?)
2) How much behavior learned as a child can be corrected as adults?
3) Can we all agree that our parents' failure just might affect us more than their successes?
What say you? Agree, disagree? To one, two, all premises? Think nature vs. nurture is a bunch of hornswoggle? Here's your chance to share. The floor is yours...