What to tell the inlaws?!

So my mother is throwing my shower as an open house and there are over 120 people invited. I wanted an open house so there isn't so much attention on me at one time and it is more relaxed. It took my mother in law almost a month to get me the names she wanted to invite. Now that my mom has ordered all the invites my mother in law wants to have their own separate shower for me for her side when they have already been invited to the original. Is it wrong of me to be completely annoyed, aggravated, etc...??? She wants a reason for them all to get together but isn't that what the original shower was for??? What do I do?