I don't want to drive 45 minutes away to pick my girlfriend up unexpectedly.
Why do you need to pick her up?
Her car broke down and she needs my help.
It's awful to not want to pick your girlfriend up when she needs your help. If you don't pick her up she'll be stranded and might get hurt.
I would rather use that time for studying than pick her up all the time.
But if she's stranded then don't you think you should help her out? She can't get home otherwise.