Email her back, tell her what you are doing and where you are going, and tell her you'd love it if she went with you. It would be a great way to start off your year together.
If she comes up with 10 different excuses why she can't change plans now, tell her those are all great reasons, but you'd still love it if she came with you anyway. If she says no, you can feel good about trying and you can go and have yourself a good time.
