Got cheated upon for a probable "arranged" marriage...

I (30M) and my ex (30F) have known each other for over five years, having both studied at the same university back in our home country. Afterward, we both pursued our Master's degrees in the UK at different times but reconnected soon after, finding common ground in our shared experiences. Over the next couple of years, we grew closer, traveled the world, celebrated milestones, and even planned our wedding for this month.

However, just five months ago, she unexpectedly ended our relationship, citing vague reasons. Despite my attempts to understand and work through the issues, she shut me down completely, refusing to engage or even acknowledge my concerns. I was left confused and devastated. I offered to work through things, and even asked if her parents were pressuring her into anything, but she denied it.

Two months later, she told me that her parents had arranged for her to marry someone else. To my shock, I later discovered that she had been talking this man while we were still together, with a crossover of 2-3 months. I dont know if its arranged or she met him herself. This new partner is wealthier than I am and has permanent residency abroad—something I could have had too, as we were both living and working overseas on temporary visas.

Last week, she married this man, in the same week that was supposed to be our wedding day. The betrayal has turned my world upside down. On top of the emotional devastation, I made significant sacrifices, including leaving my career and residency abroad to move closer to her. Now, I feel like my entire future has been upended.

I saw her wedding pictures and she seemed so happy, how easily she has done all this? Why am I the one miserable? I am depressed, cant work, cant talk, sleep 16 hours a day.