Oh it can be soul destroying.
Especially when during your training you picture them standing there ... Proud as anything... And yelling your name and urging you to the end and jumping for joy when you make it.
If you ever see someone cross the finish line alone... Be that person for them. Cheer for them. Loudly. Make noise for them.
No one should cross the finish line alone.
Because it's the glow of celebration and congratulations and admiration that cements a finish line in your heart for ever.