They both die at the end

All throughout my sleep I turn and toss.
I lose time thinking about our great loss.
You taught him to take risks and showed him not to be afraid
His death was inevitable it wouldn’t have mattered if you built a blockade
All for it to end in hospitals and flames
If only he had stayed to play your foolish board games
Even though the title reads ‘they both die at the end’
I didn't expect it and hoped that for you the rule would bend