Just Ended My Engagement

I just ended my engagement with Alex yesterday. We were together for six years and things seemed perfect until I started questioning our relationship dynamics. The more I thought about it, the more I realized that sex had become a chore rather than something enjoyable and intimate. We decided to go on an extended vacation without telling anyone and during this time, I discovered my attraction to a stranger we met in a bar. It was all very spontaneous and completely consensual; she's a woman named Casey who’s in her late twenties. The sex we had was intense and rekindled something deep inside me that Alex no longer could. Afterward, I felt both exhilarated and terrified by how much it meant to me. Is this normal? Should I be worried about my desires shifting so suddenly after such a long relationship? What should I do now?