An example of this comes from my university days. A boy who will remain unnamed and I hooked up, and we were meant to hook up again but it didn’t happen. I’m so grateful it didn’t actually, because that would have made it much harder to get over him. As it was, it only took a few weeks for me to move on but it felt like a lifetime at the time. It was horrendous at the time, but I’m so grateful that I have gotten over him! We were meant to sleep together the next time, so I’m thankful it never happened, think of how hard that would’ve made it to get over him!
Although at the time you might want it, there’s a good reason if it doesn’t. As in my example, it would’ve made the coming times harder. It’s not always clear, it certainly wasn’t at the time of my example, but it makes sense now. So maybe you’re just riding out something you’ll be thankful for in the future. It won’t be easy but if you wait a situation out, it will make sense.