If you run it bare metal (not in a dockercontainers for example) it's quite easy to set it up on a raspberry pi or other hardware. The wife would even know it's existence if you don't tell her and use a standard config in the blocklists ..give it a try ..you're gonna love it

You can set one up your network and just point your DNS request at it on a device-by-device basis. So your wife would only use it if she wanted to.

Pi-hole is pretty robust and not super hard to set up. You can run pi-hole on relatively cheap hardware, such as a Raspberry Pi 3B. I’m a big fan of Libre Computing’s “le-potato” board for running pi-hole; it’s a cheap raspberry pi clone. You’ll need some basic Linux skills but if you can follow step by step directions you’ll be fine. If you use a raspberry pi or similar hardware you’ll also need a micro SD card reader during the set up process.