I'll echo what everyone else says--she's probably certifiably nuts.
But hey, just because you ARE dating someone doesn't mean there are any guarantees...my boyfriend stood me up for my last formal (well, he kinda had to, but...) and didn't call and tell me he couldn't come until thirty minutes AFTER he was supposed to pick me up!
My roommate was sweet enough to go with me, but the night was still crappy, especially after one of my sisters spilled hooch all down the front of my beautiful dress...*sniff sniff*