Nah, "baisez mon pote" means "fuck my friend". A proper translation would be "pote de baise", although to be honest I've never heard it in use here — the more common expression is "plan cul", which minimizes the "buddy" part but can obviously cover a lot of nuances.
At least that's what I'm guessing from the TV shows, everyone I know is either in an actual relationship or does not have s*x at all 🤷
Getting angry or complaining about how someone calls their significant other and gatekeeping when it can be used is something they should've learnt to get over a long time ago.
I think fiance, wife, and husband all sound bad. I call my partner my partner, because she's my life partner. Really it's a better description in my opinion. Being a wife or husband means absolutely nothing, especially given most end rather quickly
My wife and I thought that phase was super weird honestly. It was like suddenly just by mentioning your gf/bf to a stranger you're telling them a really major thing in your life.