Dear beth,
Please don't feel embarrassed about ANYTHING. You haven't done anything wrong for you to feel sorry or bad about it.
T are not mind readers....if you feel you need to talk about it....please insist to your T that you want to talk about it.
I would say, if you are in a good relationship with your parents - irrespective of how long ago it happened....you should still tell them. Mind is weird. Sometimes, just talking about lightens your mind....it may help you.
Bring it again and again....till you are not pained by it and can talk about it freely.
Good luck!
PS - I hope those pseudo friends are out of your life for good. If you have their photos...burn it....sometimes that helps too!