screw them
Similar in use to "Screw You", only in the plural form.
Jack: John wants to know if he and Jane can come to our barbecue.
Jill: Screw them! They haven't done a single thing for us the entire time we've lived next door to them!
Jill: Screw them! They haven't done a single thing for us the entire time we've lived next door to them!