First, you will need to broaden your mind. We have always operated on the idea of one fractured star on a linear scale. The ability to alter time was introduced by those on the Source. A most troublesome occurrence indeed.

But even beyond that, here, there is the existence of multiple timelines all existing in parallel. In one we could have already succeeded. In another the tragedy could have never fallen upon us.

With this in mind, the possibilities are endless, but yet limited at the same time.