> than wouldn't that mean both wires switch between hot and neutral everytime the current changes direction?
The neutral line is connected to Earth at some point. The voltage difference is created by a transformer upstream which just pushes a 240V (or whatever) difference between live and neutral, and since neutral is tied to Earth, it stays at ~0V while the live line stays at ~240VAC.
You're right, though, that any current pulled from the live line goes back through the neutral line and they both end up with alternating current going through them.
The voltage only alternates between live (or 'hot') and neutral relative to each other. This voltage difference between the two lines is generated by a transformer and there doesn't have to be any connection between live/neutral and anything else (at which point you can just think of them as live-1 and live-2) but the neutral line is connected to Earth at some point (although depending on load and the distance to the earthing point your neutral will actually have some AC ripple on it).
The neutral line is connected to Earth at some point. The voltage difference is created by a transformer upstream which just pushes a 240V (or whatever) difference between live and neutral, and since neutral is tied to Earth, it stays at ~0V while the live line stays at ~240VAC.
You're right, though, that any current pulled from the live line goes back through the neutral line and they both end up with alternating current going through them. The voltage only alternates between live (or 'hot') and neutral relative to each other. This voltage difference between the two lines is generated by a transformer and there doesn't have to be any connection between live/neutral and anything else (at which point you can just think of them as live-1 and live-2) but the neutral line is connected to Earth at some point (although depending on load and the distance to the earthing point your neutral will actually have some AC ripple on it).