Make the sequel trilogy into a possible future that Luke sees in a Jedi vision.
Thus we can FEEL his trepidation and fear about how REAL that felt, because, in a way, it was. It’s very real, and the fact it IS real is why Luke has to work so hard to prevent it.
Make a story about his desperation to prevent that from happening. As an audience, we’d want him to succeed and find the “happy ending” that we already know won’t happen–thus creating narrative tension.