MOH - Tell me what you think

OK -

Good news 1st - my dress is in!!!!! Better news I dont have to get fitted for a few months b/c my wedding is in September ....... few more months to hit the gym.

Sorry Long
OK my Matron of Honor is my cousin. My Mom is very excited for my wedding and had begun to plan my shower like the day after we set our wedding date (she's too cute). Anyway she told my (grown woman) MOH the date several times.
FH and I get a group email a week ago with her planning a surprise birthday party for her BF (she's divorced). Fine FH notices it is for the night before my shower so he tells my Mom. My Mom dosent think it should be a problem but just wants to remind her in case - because she likes her drinks (and so do I) so she just wanted to remind her so she remembers the date via email to all of my BM not just her.

FH And I get a group email back with

I am the maid of honor at my cousins wedding.
My Aunt went ahead and booked my cousin's shower on this date .... and this time .......
I am sorry for the trouble I already confirmed with people. ( this is for JULY).

I am on the gd email - now I know the date and time of my fing shower...... I am annoyed. I have been to several showers / weddings / baby showers for her - and you cant remember the date or even have the decency to not get trashed the night before - no one asked her to move her party and now she is mad at my Mother - and I guess me???? Why would she keep me on that email do you think she forgot I was on there?

If this was me I would be mad at myself for forgetting my cousins shower that I was the MOH for - not the other way around.
What do you think girls?

I had FH's aunt ruin the surprise 1 week before the shower, and her response was, 'don't tell anyone i told you.'

I was royally pi$$ed!! I had wanted it to be a surprise so badly. Then, all she gave me for the shower, was a pillow. A PILLOW. Are you f'in kidding me????!!!!???

I feel your pain. I'd let her know how pissed you are.