Jenn and I just celebrated 5 years together. We had an inexpensive dinner at a little local bistro. I bought her a simple silver ring from a local jewelery maker. She got me a 6 pack of an IPA that I haven't tried yet. Neither of us expected anything from the other, both were surprised and happy, and all told, less than $80 was spent including dinner.
Recently, I bought her a Nikon D40x as a thank you for her help in putting me through school. She certainly didn't expect anything from me for my graduation.
Gosh, let me tell you, I'm just hating life right now. It sure sucks doing something nice for someone . I know you're a little bitter on the subject, but not all gift giving is born out of begrudging obligation.