that's all I need

(something) is all (one) needs

Said ironically to indicate that this is something one doesn't want or need at all. Great, more interns to train—that's all I need! We're already struggling to keep up with everything our kids are doing, so a house full of relatives is all we need right now.
See also: all, needs

that’s ˈall I need

(informal) used when something bad happens in a situation which is already bad: The car’s broken down? That’s all I need!
See also: all, need