Do we get another chance

Plato said that each of us are a matching half

of another human whole;

that love makes us search for that half 

which completes our soul. 
Apparently, love is supposed to heal  
the wounds of human nature. 
Meaning that there is only one person
fit for another-
the notion of soulmates
is two unique and one-of-a-kind lego pieces 
that only complement each other, none else. 
 I always used to say that soulmates were like 
          the perfect lock and key, 
           but look, sometimes you lose the key, 
           so the locksmith makes you another one

         and it fits, just like that:

a brand new replacement. 

So what is it then? One for another?

Or do we get another chance at true love?