Am I being unreasonable?

So for over a year now I’ve been saying I wanted to go on a cruise for my 25th birthday. My initial plan was to go by myself because my friends and family aren’t that reliable when it comes to stuff like this. I had a cousin who I mentioned it to and she wanted to go. We booked the trip and paid for everything but the cruise line is requiring everyone to be vaccinated. Initially you just had to have a negative test. I’m vaccinated but cousin had already said she didn’t want it. Would it be wrong if I went without her? I’m not mad at her for not getting it but I don’t want to change my plans and I don’t want to push her away. Any thoughts?