help me for choosing a gift for my girlfriend on her bday

I have a nice idea in giving her a gift, surprise her a dinner date on her birthday. First, show her that youu don't remember anything that day until she became angry with you, then, try to communicate with her friends to invite her to the place where you have planned everything. SInce, you have talked to her friends, invite them too and have a cool party with all of them!

It should be something personal that she knows only you would buy it for her and only her. If you don't know what that is, you should be paying more attention to her.