Baseball Baby Shower Favors My Boyfriend's Sister Is Having A Baby Shower And Inviting His Two Ex-wives. To Go Or Not To Go?

My boyfriend's sister is having a baby shower and inviting his two ex-wives. To go or not to go? - baseball baby shower favors

His family is still (to their ex-wife in the vicinity who has a son with each). I do not feel comfortable with them - a middle way that goes well, baseball games, concerts, etc. - but is his father's house, another story. His family knows how I feel, but not so for almost 8 years. I want my voice heard and is not the best way to do that?