Avocado,
The Gemara (Sotah 2a) says that Hashem gives each person their bashert “l’fi maasav.” In other words, who your bashert ultimately is depends on your actions (mitzvos, aveiros, etc.). It seems to me that one of those actions is rejecting a match. So if a person rejects their bashert, then everything needs to be reworked and someone else might become their bashert.