Not easy is it, Buying love never really works for long..I am sure you have found that out, the past is done what you do now is you take a step back,if they are rude you do not see them until they are respectful, you can just do it, or quietly tell them that you will only see them if they are respectful. Dont concern about the ex she isnt part of your life, really their father could have spoken to them and told them this is not permissable, in fact it is he that would be better .telling them ,no rudeness, respect please.It is possible that a few years ago they were jealous, too late now, so be pleasant be kind, but they have to return it ..Good luck