Hi, i was like you bu in worse: my fiance suddenly doesn't want to marry me & worse, at the same time,she announced me that she will marry with an other one.
At the moment, i hated all women on Earth for such this bad behaviour,(i know this is wrong), playing me like a tool and it was not the first time.
But see the good sides:do you prefer to separate before or after get married ? Before is better at all.
And such behaviour is a proof that love is gone, and she dont earn you.
In France, we have this proverb :One lost, 10 found