Nancy, I am in the same position as you. Right down to the tearing up of the nasty carpets and fixing the bedroom door she smashed in. The only true difference is your difficult child is much more social than mine. Sometimes I wish mine were, other times I am thankful.
I have accepted that difficult child is a nasty person. One I will really try not to live with for much longer. I hope she can be happy one day, but she will not steal my happiness forever.
Acceptance is a freeing thing. It does not mean we give up hope. They are only 18. Their learning years are ahead of them. We wish they would learn the easy way - by listening to us
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but sadly they choose the hard road. Is that horrible? No. Will they have a more difficult time getting success in their lives? Yes. Is it our fault? No.
She has accepted it. You can, too. Accept that she is not who you wanted her to be. Accept that you do not wish to live with her. Accept that she will have harder times ahead. I would not accept a drug addiction or a criminal act, but we sure can accept a personality trait - even if we do not like it. I have said for years if difficult child were my husband I would have divorced her long ago. I can't be around people that are negative like her.
Yes, you should focus on you now. She will make her choices anyway, so you might as well put your energies into you and husband.
I don't hold out much hope that my difficult child will stop by with a successful husband and well behaved children one day. My true wish is that I could move far away so I only had to endure the chaos a few times a year.
It has never been easy. It may never be easy to be around our difficult children. We have a ton of bad memories to carry with us. Accept that. We will always know what they put us through - even if they never do. Forgiveness will come one day. When they call us to see how we made such and such dish that they remember from childhood. Someday they will call just to see how we are doing.
I sure do not have all the answers, but I do know that when I accepted that difficult child was a miserable, selfish, lazy child - I relaxed a bit. She told me the other day 'why don't you think about someone other than yourself for once' - I swear my mouth fell open. She hung up after that so I had no response. I honestly would not have had anything to respond back because it is sooooo far from the truth and reality and I KNOW there is no reasoning with her. So, let her think that. I don't care if that is what she thinks. It makes no difference to me.
Anyway, I am rambling a bit. I do understand where you are and I hope you can find a way to accept it.
HUGS!