I agree, that Nade is selfish, self centered and immature. But who thought her those characters? Her dad and her grandparents alone. When her mom passed away her dad wanted to fill the void in Nade's life that his passing wife left behind. His intention by all means are pure but nonetheless it doesn't make it right. Nade grew up in the environment of a spoiled brat all her life. It's hard for one to change over night when that is what you are accostumed to no matter what the age is. The fault lay sqaurely on the feet of those around her. Her dad and grandparents probabaly never taught her how to share it's always been mine...mine...and more mine. Yet her dad knew how his daugher is, how emotionally needy she is he still managed to surprised her in the worst way. He pretty much say...hey,honey meet your new mom. Really? Can he not be a little more transparent about it? No matter from what side you look at it. It was just unfair to Nade.
Sometimes they say, when there's a crisis or something important happen you remember those important to you most. When Mon had her baby, Nade became 'anybody' not a somebody. It might be a one moment thing but it was a moment of weakness for Nade when she felt like everything in her life is slipping away from her. In life it takes but one crucial moment for you to doubt those around you.
As for Chon, I never like it when the Pra'ke marry the Rai. It just leave a bad impression on me. Because emotionally he is bound to cheat on his wife with N'ek. He could be just as an effective parent without marrying Thip. Having two parents not loving each other is not a home.
Nade marrying Tansik is her greatest mistake. But there are times when everyone around her needs her to make that mistake to grow as a person. She can't be treated with kid's gloves all the time. Her dad can try to talk some sense in her but he can't order her not to do it. That is her decision alone and even if it's not the correct one it's hers to make. She'll never grow up if she can't take a leap of faith and do what she felt is the right thing or the wrong thing for that matter.
I honestly, think Nade will continue to be spoiled. Once Chon and her get back together he'll probably love her to death because he's afraid he'll lose her again. She'll be wiser I'm sure but at the same time she'll be love more by Chon. So, frankly she'll never be completely out of her spoiled stage because there's a person out there willing to spoil her.