Syringer, if you have ever been in a serious relationship you would know that for SOME girls, you must celebrate the "anniversary" for everything...1 month, 3 month, 6 month, 1 year, etc.....especially during the first year when it's all......well, good. :Q Afterwards its not like you celebrate an 18 month anniversary. This is just standard girl crap that costs us extra money.
Then again maybe you were just lucky and had a really down to earth type.
Anyway, just take her out some place nice and be extra romantic. If you're throwing in a gift in with all that, don't spend more than 20-30 bucks IMO.
$500? put down the drugs son. she might ditch your ass in a month (or you might grow bored of hers)