How do I see who someone is talking to on Facebook Messenger?

Ugh, I’ve been down this rabbit hole. All those spy apps cost a fortune, seriously. They want you to pay a monthly subscription, and it’s a total rip-off just to see who someone’s texting.

Honestly, the only free way is to just peek at their phone, but who can get away with that? lol.

Does anyone know of an app that’s a one-time purchase or has a good deal going on? I’m not trying to break the bank just to see some chat logs.