My Sons GF is Disrespectful!?

What I would say is, firstly stop getting things for her. You said you bought her jewellery- she expects things from you now, and so, is not grateful for all you do for her. You also need to stop keeping contact with her family; you said you got her dad a job- that's nice of you but the impression they now have of you is that you're a sucker. I think if you let your son spend a bit more alone time with this girl, he'll see what an emotional mess she is, and he'll probably want to leave her- guys don't like that sort of rubbish, understandably. And I think you do need to start being a bit rude. Not very, but you need to display your authority. Like, when she's rude to you, you give it back to her- for instance when she complains about what kind of clothes you're getting your son, say, "Well, when you pay for it you can dress him up however you want." She's obviously a bad egg so I hope she'll go away soon. I think if you sit down with your son and just warn him about her, it would be good. BUT be careful that you don't seem bossy, else he'll do the opposite and go back to her. Just mention that she has wild mood swings and seems menopausal but don't lecture him about how he needs to break up with her. Hopefully your son will leave him in time- good luck.