I see this a bit (A BIT) differently than Newlywed2009: I think this was some kind of disagreement between your fiancee and your mother, and your fiancee called to "straighten her out."
I would have dumped you. It's disgusting for a man to even threaten to hurt a woman. Do her a favor and break off the relationship so she doesn't have to deal with your threats anymore.
As far as "right" and "wrong"... Even if the other two didn't handle the situation well, your response was over-the-top horrible and unacceptable. Please seek help for why you reacted this way. A woman with self-respect wouldn't tolerate you.
Not very often we can read about both sides, if they are in fact two separate people (from another board):
My fiancee and I live together.
If this is your fiance's side of the story, it seems that your mom is overly sensitive to end up crying over something like this.
Folks, if both of these posts were from the same poster, then rav411b is ls33--the woman in the incident.
I'm just struggling so much