I'm so upset right now 😭😭

So I need to ask y'all if this even a little bit okay. So, getting on with it..

I'm engaged to man with two daughters. We have none of our own and I treat them like my own babies. They're three and five.

My mother is taking them to a birthday party tomorrow, and my fiancee knew about it, but didn't tell me.

Let me explain why. My uncle raped me for years 9 to 16 years old. This man and his wife will be there. We aren't allowed to go because of this, but my daughters do? Nobody knew he was raping me until I told my therapist but this is okay? Everyone thinks I'm over reacting..