Could really use some advice
Okay. So I'm going to give you some background before I get to my problem. My mom had me at 16, and my biological father terminated his rights a few years after I was born. My dad adopted me soon after him and my mom were married a few years after the termination of my biological dads rights. Needless to say, my mom and dad do not like my biological dad. In fact, they hate him. Around 5 years ago, my biological father got back in contact with me and asked to be apart of my life again. I accepted, and we've been in regular contact since.
Now for my problem. My wedding is coming up and I've been making out the guest list. My parents found out that I plan on including my bio dad and some members of his side of the family (my grandfather, aunt, etc) as well. My parents became really upset at this, even though my bio dad, nor anyone on his side has a role in the wedding; they would simply be guests. They feel so strongly about not having my bio dad there, that they told me if I'm inviting him or anyone on his side, that they would not be attending my wedding, and they would not allow my siblings to attend either. Not only that, but they would be "done with me" as in kicking me out of the family, etc.
I know that they're not bluffing either, because they've done it before when I decided to go to a Christmas on that side.
Obviously I've been very upset about this. I don't know what to do. If I give in to what my parents want, then people that I love won't be at my wedding. But if I don't give in, then people I love won't be at my wedding. It seems that I lose either way. I want to just have my wedding and be able to invite whom I want to attend... am I being unreasonable? What should I do?