Sorry, this is my first post so I’m not great at writing. Sorry if it’s messy. I’m 42 and work as a barista in Udon Thani (my hometown). I’m a pretty low-key person, don’t show off much, but right now I’m really shaken up. Seriously, I’m so confused.

It started with small behaviors I’ve been noticing for almost a month — actually about two weeks I started feeling something was off. My partner (we’ve been together almost three years) said they’d come help at my shop sometimes to earn extra cash and have been staying over at my place more. I was happy, because I wanted them to help clear tables, wash glasses, sometimes we go grocery shopping together. Like last night we even went out to buy veggies around 8pm. Life’s simple.

But the problem started when a strange guy became a regular customer. He calls himself “Nong Git” — he’d sit and read, talk with my partner for hours, sometimes pay for my partner’s drinks and wouldn’t let them pay him back. He also calls my partner a lot and I saw the screen show the name “P’Git” when I was behind the counter. They smile at each other, talk like they’re really close, more than just customer and shop owner, which made me a little uneasy.

Then yesterday I accidentally saw a note on my partner’s phone briefly — they saved this guy as “Git_teacher” and there were two transfer slips from last month. I didn’t look closely but my heart started pounding, felt like someone stabbed me inside, went totally quiet. There was also a tiny piece of blue lip balm in the cashbox. I don’t know when it got there but once I saw it I couldn’t stop thinking about it for like half an hour.

I don’t like assuming the worst, but other things happened too — my partner started locking their phone when I look, hiding chat histories, deleting some stories. I chat with friends at the shop a lot but nobody’s ever paid like this before. Am I being petty? Or is the guy an ex-student or there’s some teacher-student thing I don’t get? I’m so confused.

What’s making it worse is I want to talk directly but I’m scared it’ll blow up. Scared they’ll get angry, scared it won’t end well, scared I’ll look paranoid. I don’t want to hurt anyone without solid proof, but I can’t stop wondering if I’m being fooled or if it’s just a harmless friend I don’t understand.

Question: how should I ask? Calmly? Or confront them right away and ask straight up? I’m scared the other person will get defensive and it’ll turn into a big fight. I’m really scared, honestly.

Has anyone been through this? Please share ways to have a calm conversation that actually work. I don’t want to jump to conclusions too fast, but I can’t live with the doubt forever. What do you all think I should do?

P.S. Thanks in advance for any advice. I read every comment T_T