? give up?

what to do i have 4 kids and 2 of them just dont care... i have tried ..time out .. takeing EVERYTHING out there room ...yelling...knees...poster boeard with good and bad behavior...consistancy... there father and his family has never backed me up ...but went against me when i corrected the kids.. we divorced 6 years ago and i cant get them on the right track ..all i can say is I love my kids to no end but at the end of the day i go to my room every day and cry my @ss off because seriouly NOTHING works i am thinking about haveing them live with relatives . they create HAVOC in the home .. i dont want to do this .. I am begging someone to plzzzzzz help me!!!!!!! I cant take the disrespect from them nomore and the NO's from them when i ask them to do something...they seriously destroy the house and will not pick up after thereself!!!!!!!!!