Hey everyone, first time posting so sorry if this is messy or I ramble. I'm 24, doing a master's at a uni in Samut Prakan, drowning in my thesis project due next month, and I've been living off instant noodles at 2:30 a.m. a lot lately. Something happened last night and I'm still shook.

Basic background: me and my boyfriend have been together almost two years. He's hardworking, studies and does a little part-time tutoring. I'm doing research. He's 26 and works at a private company in the city. In his free time he goes back to Samut Prakan and comes to see me at my room or a cafe near the uni where I usually sit and read (he usually orders a hot latte and puts his notebook and mechanical pencil in the corner of the table). Our relationship seems normal, but there are little things that bug me — like he likes to keep his phone in his pocket when we're together, reads messages and replies slowly, sometimes says he's going home but then says he'll meet friends first. When I ask where he is he answers tersely “almost there” with no details. I tell myself he just doesn’t like chatting a lot but it still annoys me.

Last night was the real turning point. The night before that I was at the library and came back around 11:10 p.m. He picked me up and took me back to the dorm. On the way he opened his phone and smiled weirdly at something; I just watched and didn’t think much.

When we got back, I put my bag down and had to send a group assignment urgently, about 40 minutes, so I asked to use his laptop for a bit. He left his phone on the table where it was obvious — the spot we usually put coffee cups or a small keychain. It wasn't locked. I didn't want to snoop but my curiosity got the better of me and I scrolled through his chat (sorry, I know I was wrong). The screen showed a LINE chat with a name I didn’t know — they'd been talking for like 3–4 months. The profile pic was a girl with a fresh look, not heavily edited. Scrolling I found messages that were more than “just friends,” like clingy lines, compliments, and a small couple photo she sent as a playful “miss you” thing. My boyfriend replied at length, explaining work days and when he'd be free, and there was a plan to meet last Saturday — but he had told me he didn’t go anywhere. The chat even said “let’s meet,” which didn’t match what he told me.

Silence.

I grabbed his phone and asked straight up who she was, what kind of friend, speaking quietly. He looked surprised and said, “an old friend, we chat a little, nothing.” But his face went red and he tried to take the phone back. I'm genuinely confused — this doesn’t seem like a normal friend.

Another thing that throws me off: he said there was nothing, but on Saturday morning he left the room early saying he had urgent work. I saw that girl's story — a picture of a coffee with her tagging his name, and the shop name and time matched exactly when he said he had urgent work. Felt like being lied to. Why would it line up so perfectly?

I checked her social a bit more. No clear couple posts, but she posts ambiguous stories all the time — like a photo of flowers at a cafe with the caption “waiting” and she tags him. I'm like, what is happening.

I’m not usually super jealous but this is bugging me so much. It’s heavy on my mind, like really heavy. I keep asking myself if I’m overthinking or trusting my gut, but I’m scared that if I accuse him and I’m wrong he’ll think I’m controlling or overly jealous. I’ve been losing sleep for two nights.

I haven't confronted him properly yet because I'm scared of a huge fight and making things worse. I want clear proof first so I can talk calmly, but I can't keep it inside — every time I see his phone my head explodes. Sometimes I want to ask directly but I’m scared the answer will hurt worse.

Am I being petty? Should I let it go? But if I let it go and it was real, I’ll regret it later. I’ve been going in circles all day T_T

Has anyone dealt with this before? What did you do? Be straight with me — confront him now or gather evidence then talk? Will he lie? I’m scared he’ll admit it and it’ll hurt more. My heart races all the time and whenever he’s gone I check his LINE like a crazy person lolol.

Sorry for the long messy post, first time making a thread. P.S. If anyone has tips on how to talk without hurting each other, please tell me — I’m scared of my own harsh words.