I'm sure I am being a miserable old cowbag here, so feel free to tell me so 
BIL (DH's brother) and SIL are celebrating their PFB's 2nd birthday party with an invitation to all the family to come and celebrate. My problem is that while most of their family is relatively local, we live about 300 miles away. I can think of SO many things I'd rather do with a weekend than a 600-mile round trip for a toddler's birthday party.
AIBU?