rusty wires

No that's not my **** name. My headlights went out, so troubleshooting, found that one of the contacts on one of the lamps was almost broken off. I replaced the lamps, and then it was still not working. Only the brights would work. So I was getting a good voltage reading up until about 8 inches from the lamp connector, and there it was stopping in its tracks. I probed it to a specific spot, where the wiring looked fine. Cut back the wire, and found the wires were all rusty and brittle. WTF. I've never run into that much before. I guess it's time for a headlight relay upgrade, and replacing at least this run of wire.