I usually have the reverse problem - DH was always used to dressing WAY up for family events, etc. I remember trying to convince him (to no avail) that my family wears jeans to most functions (except weddings, etc.) - I'll never forget the look on some of their faces when he walked in for his first Christmas in a 3-piece suit and couldn't understand why no one else was dressed "appropriately"! 
He's getting much better finally, but he's always eager to break out the suits and ties. I'm usually the one who gets nervous about dressing up enough for HIS family's functions - I'm much happier on turkey day in comfy, expandable clothing than in a fancy dress!}( (My mother tells me not to complain, seeing as she has a hard enough time convincing my father to wear CLEAN clothes!)
He's getting much better finally, but he's always eager to break out the suits and ties. I'm usually the one who gets nervous about dressing up enough for HIS family's functions - I'm much happier on turkey day in comfy, expandable clothing than in a fancy dress!}( (My mother tells me not to complain, seeing as she has a hard enough time convincing my father to wear CLEAN clothes!)