If you live in Canada, you should be posting from that website.
Find a different physician. What your physician is doing is actually illegal under HIPA, Canada's Health Information Protection Act.
If you are really wanting to stay with this doc, then give her one more chance, making it clear that this is inappropriate. Otherwise, it's going to come down to staying with the doc and having your information illegally shared or changing docs.
This doc shouldn't even be tellng your family about your flu shot or your colds.
When she asks you at the end of your appointment if there is anything else, say:
"Yes, and it's really hard for me to bring up because you've been my doctor my whole life, but my parents are finding out information about my medical visits and I'm really unhappy about that. I'd really like to ensure that all my medical information stays private and I'd really like to keep coming to you since you are an excellent doctor."
Don't even give her the option of figuring out what's ok to tell your parents and what's not. So no being a wuss and saying "Flu shots and colds are ok, but..." Everything should be off limits and that should be a pretty easy line for her to avoid crossing.
If she can't remember after you tell her this, then she's not any doctor that I would want to see. This has been a law for 8 years. If she can't keep up on 8 year old law changes, I wouldn't trust that she reads journals o r keeps up on new treatments, new illnesses, new studies, etc.