I'm planning to "ruin" my girlfriend's birthday
How could you ruin your girlfriend's birthday?
Yes, I'm planning to drive her to the verge of a nervous breakdown.
You shouldn't ruin your partner's birthday. Whatever issues you may have with them should be wait to be dealt with on another day. Otherwise she will be extra upset about you upsetting her on her birthday.
She deserves this.
Your anger at her doesn't justify ruining her birthday. Don't do this.