Sorry, this is my first time posting and sorry if it's messy — I'm terrible at writing T_T

It's a long story but I'll try to make it clear. I'm 29 and work as a barista at a small shop in a market area in Phuket. I've been with my boyfriend (maybe soon-to-be husband?) for almost three years. We fight sometimes but usually we get along, and we were planning to get married in about four months — a small wedding, not many relatives, we like simple things. But right now I'm totally confused and feel like the world tilted.

He's usually quiet, hardworking, good at saving, seems like someone ready for family life, so I wasn't too worried. But two nights ago, around midnight at about 22:15, I accidentally saw his online account unlocked (I'm sorry, I know I should respect privacy). There were lots of withdrawals over the past year that didn't look like regular expenses. At first glance I thought they were necessary bills, but when I looked deeper it was money transferred to online collectible sellers and some given to friends who run a small betting circle on football. There were also big orders of collectibles sent to a rental room used by another person. I was shocked.

It wasn't just once or twice — it was consistent, almost every week for months. I roughly calculated and it's not a small amount, especially money he'd been saving for the wedding and for buying our little house together. Altogether it's basically almost a year's worth of savings. Am I overthinking that he might have some other financial plan? Or does he just have a ridiculously expensive hobby? I don't forbid hobbies, but I understand finances, and it hurt that he didn't tell me.

My feelings are all over the place — angry, confused, and this weird loss of a little trust in his transparency. We often talk about the future, what direction to go, how to save, where to spend the big lump sums. But after seeing this I'm not sure if he sees me as a partner in planning or if he wanted to keep secrets because he was afraid I wouldn't understand.

I had an ex who hid money stuff and it ended the relationship, so that feeling came back. But I'm older now and understand people might have past issues. Why did I expect him to be open from the start? I also make mistakes, but hiding spending that affects our shared goals made me question a lot.

I tried talking to him directly twice. The first time he was shocked and defensive — said they're just collectibles he's been buying for years because he likes them, and some friends borrow from him occasionally. When I mentioned the numbers he went silent and said he can handle it and I shouldn't worry. I believed his voice, but his silence and avoiding eye contact in ways he used to be open about made me uneasy.

The second time I tried to stay calm and not accuse him, just said I want clarity about the wedding budget and our shared savings. He said whatever makes me happy and said he'd talk to his friends and return the money bit by bit. Like… I would be glad if he actually returned it, but why secretive? Why not say up front that he had small debts or helped a friend in need? He didn't say anything.

Part of me thinks I come from a not-very-rich family, learned to work and save for stability, and now wonder if the guy I'm going to spend my life with is walking a different path — or am I overthinking? Or do I not understand that for him collecting things is a form of happiness and he didn't want that happiness taken away before the right time to tell me?

There's another thing I just noticed: when he pays for something big he avoids my eyes like he's afraid I'll disapprove. It's strange. He's usually honest, but with money it's like someone else takes over. Am I imagining things? I don't know.

Sometimes I blame myself for not noticing sooner or not discussing money deeply from the start, but I also feel that if we're going to share a life we need more transparency, not secret corners that affect our future.

Friends who are married or have dealt with this, please share. Should I give him a grown-up chance to sort it out and teach him to be more open? Or is this behavior a big red flag and I should step back before the wedding? What kind of financial rules should we set up together? Is there a way to fix this, or should we postpone the wedding?

Sorry again if this is long and messy. I still can't believe I'm here lolol

What should I do? The keychain is probably still in that small rental room box, but trust… it's a bit gone. Can it be fixed?