WWYD?

My best friend is having a house warming party tomorrow and wants me there. I have 2 kids, 1 is 21 months and the other is 18 days old. Before I had my second I said I’d go and now that he’s here it’s different. I’m not sleeping too good(as we all know), he’s a fussy baby, hates his car seat, I’ve not gotten the hang of 2 kids just yet. Her house is 56 minutes away and I’d be going alone since my fiancé has to work. Yesterday I tried going to the store alone with the kids and it went so bad I ended up in the parking lot breaking down crying. I don’t want to hurt her feelings but I’m also just really scared to go.