as a general rule of thumb, all teenage children are horrible, especially boys. (Funnily enough, it wasn't always this way; but it is now.) Awful as it is to say it, I think you should distance yourself from them - the older one at least. As others have suggested, tell him you choose not to be treated this way and will not see him again until he learns respect. And make it plain to the younger one that the same will apply to him at the same age. It's dreadful when children and parents fall out, but it does happen, and I think after years of doing your best for them, it is time to put your own feelings first. This is not something you need to feel guilty about; nobody has to sacrifice their sanity for the sake of obnoxious children.