[Paul F]

No, they do not share wires or fibers. They may occupy the same pole, or run through the same group of conduits underground, but they do not share the same wires.

Geek answer:

Wireless is rarely used except in very rural areas for internet, phone, or TV (ignoring WiFi here, which is a different subject).

When they built your neighborhood, the telco and the cable company paid the developer to put their fiber/copper in the ground for their exclusive use.

Cable companies use coax or in more modern systems, fiber and coax. A fiber runs out to a neighborhood and supports 200-500 houses. From their, they run coax to the houses. This is a completely separate network from the telco.

Telcos use 3 configurations
- Twisted pairs (the stuff you see in the house)
- Fiber to the neighborhood and then twisted pairs to the house
- Fiber directly to the house.