I doubt the story will vary much form person to person.
Thankfully DH is still alive and active, so the lowest point in my life was the loss of my sister in a road accident when she was 45. My parents lived to a great age and were ready to go, so I feel that that was nature taking its course, but my sister, close to me in age and close to me in other ways as well, was by far the worst that has happened to me and the thirty years that have passed since have not changed this.
Best, like others, my 2 dear children, and, now 2 deat grandchildren, but I do not wish I had had more. Like you it interrupted a career that would have gone further without them, but I still did pretty well.