The initial stage of love leaves us to believe everything is and should be perfect, we should agree on everything and all will be smooth.
This is simply not true. No matter how long two people are together, no matter how much they love and care for each other, there will be disagreements and topics you don't see eye to eye on.
That is healthy, that is normal.
It's important to understand what those topics are, that it's OK to have different perspectives, and to validate and respect each other's feelings.
Now if the cons outweigh the pros, it's not a relationship worth staying in.
Regarding braking too late, accelerating too quickly, following to closely, she does realize what car she's riding in, right?
Good luck, stay strong, drive and love safely.