lebbie

I don't know how to react to this sittuation. My fiance's friends, and his brother too have begun to invited my fiance's ex-girlfriend over to parties. No one ever lets us know she will be there. So when me and my boyfriend show up---there she is. No one has stopped and asked how my fiance or I feel about this. Am I over-reacting at becoming upset about being placed in situations like this again & again. Help.