Hi everyone, sorry — just joined this forum for the first time so a bit nervous, and sorry if I write messy or make no sense. I'm 38, work at a factory near Phuket town. Simple country guy, just wanna vent a bit.

So I've been with my girlfriend (let's just call them “they”) for over 2.5 years. We're living together but not married. Things have been fine for a long time, but lately little things kept nagging at me until yesterday, which made me start doubting more.

I usually leave early for my morning shift, around 5:10am. They sell food at the shop near our soi — like made-to-order dishes — and finish later than me. A lot of times they send me pics of food or funny stories to read before bed, which I like, it’s funny. Lately they always seem to carry car keys and a red plastic keychain in their pocket, like a tiny detail I noticed.

But yesterday I accidentally opened their phone to check a message they sent to their mom (their mom called late and they forgot to hang up) and I found a chat in another app I hadn't really paid attention to — messages from someone nicknamed “Boy” (not my friend). There were heart stickers, soft greetings, and some lines where they replied gently. Reading it felt weird, but I didn’t see the full picture. Just short lines and a photo from an angle I wasn’t used to — the pic timestamp was around 03:12am. The photo was blurry, just part of their face, a shirt, and the back of a car or something.

My head ran everywhere. Happy? Not at all. I went silent. Super confused. I only looked at the phone for like 7 minutes then put it back — I wasn’t trying to pry but my heart was racing like mad. I couldn't sleep for over an hour after, kept obsessing about it.

There were small signs before — they started turning their phone off more often after work, came home later than they said sometimes and said coworkers were helping with events or an outside person helped at the shop. I believed some of it but was suspicious. Money-wise nothing odd, no strange expenses, but people can change, right?

I’m not an insanely jealous guy but I’m not someone who lets stuff slide either. If there's clear evidence I want to talk, but right now I have no clear proof, just a gut feeling and a few messages. I'm afraid if I force things and it’s nothing, I’ll break the trust we have. But if I leave it, it might get worse. If I confront them straight up, how do I even start? Like… should I open the chat and show it to them right there?

Am I overthinking? Should I talk to them directly? How should I start? Digging up the chat feels like invading privacy, but keeping quiet will keep bugging me. I'm tired but I don't want to be someone who constantly picks fights over everything.

Anyone been through this? What did you do so it didn't hurt each other unnecessarily but still got a clear answer? What should I do, folks? (Oops, I mean guys ㅋㅋㅋㅋ) P.S. Sorry if my wording is all over the place T_T