My parents don't know my SO' parents and my parents are divorced -it's been almost 11 years since their divorce-
We don't want our parents to meet on our wedding day, that would be too weird and would probably cause more than just one awkward moment.

We are getting married the 9th of August. My mom's Bday is on the 7th so we -SO and I- thought we could have a special dinner on the 7th, to celebrate my mom's bday and for our parents to meet. I asked my parents and they are OK with the idea. The thing is… my father has a 10 years old daughter and he will bring her with him to Cartagena. I don't have anything against her or hold any kind of resentment towards her, but I certainly am not interested in being friends with her. I am civil and all and the times my father has asked me to go with them somewhere so that she is not doing activities alone, I have gone with them.

Now, the story is completely different with my mother and I understand her very well. My mother suffered A LOT for many years because of my dad's behavior. He treated her poorly, cheated on her more than once, took her for granted, etc. She stayed with him despite his awful behavior because she loved him and because my brother and I. She decided to get divorced when she was getting ill because of the situation and because she found out my dad got pregnant the woman he was cheating with at that time. My brother and I were old enough to understand the situation and we witnessed my dad's poor behavior for many years that we agreed with my mom's decision. We supported her and stood by her side, we still do.

The things is: I don't want my dad's daughter to be there the evening our parents are meeting. It's my mom's bday and having that girl there would remind her of the awful times and it could create a weird atmosphere. I know my mother very well and I know how she feels when that girl is around. I honestly wish my dad wouldn't bring her to our wedding at all, but this is something I can't ask him to do because he is also giving us money for the wedding and I would feel bad. I am ok with him taking her to the ceremony and stuff but not to the dinner on the 7th. It's my mom special day, I don't want it to be ruined!

I haven't told him anything yet because I simply don't know how to tell him without making him feel bad. On friday one of my aunts from my dad's side called and asked about a hotel option for my dad. I talked to her and this issue between the things I told her. I now think she told him already and that's the reason why he was acting cold today when I called him. I get the feeling he is mad but is not telling me anything.
Leaving the girl with somebody while we are at the restaurant wouldn't be a problem. Some of my relatives from my dad's side will be already there, including two cousins around her age. She can stay with them for a few hours. Maybe I see it easy, but perhaps they don't because sadly my relatives from that side including my dad, like to complicate everything and to talk more than they should.

The past few days I have been feeling a bit down and somehow desperate. Like I want this to be over soon, like I can't wait to start our life together, to run away from all this mess, from all the negativity around, from all the complicated people, run away from everything… start from zero!

What would you do if you were in my situation? how do you think you would handle it?