A little backstory:
My family is fuc..... a modern family. My parents split after 14 years of marriage when I was 11, both of them remarried and my Dad had a child with his wife and has since divorced that wife and is now dating a new woman. When my brother got married, he was still married to wife #2 and at the reception she made QUITE the point to state that she was my Dad's wife, that my Mother had no place sitting with HER (my father's family) and promptly booted my mother, her husband, my stepbrothers, their wives, children and my stepfather's parents from the "family" table. My brother said nothing to my stepmother and my Mom and that whole side of the family left the reception shortly after and it was a little tense for about a year. Since then, we see my stepmom (Dad and her split in 2009) once a year. We all have Christmas Eve together: My former stepmom, my former stepmom's new husband, me, my FI, my Dad, my Dad's girlfriend, her kids, my sister, my brother and his wife and their boys. Slightly ridiculous, but whatever. It's not too awful of a time, but literally, that's all I see them.
Fast forward from 2007 to 2014. My former stepmother got married in August 2014 and invited, for some odd reason, myself and my FI (Along with the rest of my clan.) We attended the reception (not the wedding), gave a gift etc. Overall, not an awful time. But still weird. It's nice we can all get along, but it's a little odd.
I sent out my STDs last week for my wedding in May. I immediately get a phone call from my Dad "Why didn't you invite X? (your former stepmother)" "I didn't realize that I was under an obligation to invite X to my wedding. I'm not sure why I would. I don't really consider her a friend. Yes, I went to her wedding for my sister -- not her." "You should invite her and Y. Her feelings are very hurt you're not inviting her." "I'll think about it Dad. Thanks."
My parents are paying for most of the wedding. My mom is gifting more than my Dad. I asked my Dad for a list of people that I should invite on his behalf and he didn't give me one. So I'm thinking the ship has sailed. He's throwing a fit like a child (He apparently doesn't recall how terrible his wife was to me when I was a teenager). I also want my Mom to have a fantastic day as well and not relive my brother's wedding. I'm frustrated.
Then my Dad asks if I'm inviting his girlfriend to my bridal shower/bachelorette party. I am obviously not hosting it -- the mothers are and my bridal party. Apparently his GF thinks that she should be invited (obviously she'll be at the rehearsal dinner/wedding etc). Her and I are not friends in the slightest. When did my Dad become such a premadonna? Help.