Do I cancel or go?

I live with my fiancé and his parents. My sister invited me and my mom to go to her florist appointment for her wedding. It’d be nice to see her and also get an idea for my wedding, about flowers and cost ect.

I originally said yes and my mom and sister agreed that we’d meet at my fiancé’s parents house and leave a car there and take one car.

My fiancé has been pretty cautious about the virus but the last month has been pretty much “you do you” as far as me telling him I’m going shopping with my mom or going home.

My only hesitation is that it’s 3 separate families in the car together. My moms fully vaccinated and my sister social distances/had covid a month ago.

My fiancé’s sister is visiting the weekend and she’s pretty cautious about covid and has set rules we follow when she’s here(full shower after being in a store, changing clothes ect.) She’ll be at work while I’m gone though.

Part of me really wants to go but another part wants feels like I should just say I can’t make it anymore.

What do I do?