Frankly you're "friend" sounds kind of dense.
You had to see a doctor and follow a course of treatment. He'd have to know your parents would have found out, and he'd have to have assumed that his parents would have likely been informed at some point as well.
That of course assumes he wasn't dense.
I'm not sure why you maintain a friendship with someone who pulls this crap, repeatedly with you. As for why, it is likely immaturity paired with difficulty grasping social convention. Or maybe you are (in his mind) the lackey / sidekick who he treats like crap as a mechanism of proving his own coolness. Metaphor: You are Milhouse and his is Bart (in his mind)
Straighten him out, I assume there is a reason the two of you are friends. If that is not an option drop him. Life is complicated enough without people like that in the mix.
You had to see a doctor and follow a course of treatment. He'd have to know your parents would have found out, and he'd have to have assumed that his parents would have likely been informed at some point as well.
That of course assumes he wasn't dense.
I'm not sure why you maintain a friendship with someone who pulls this crap, repeatedly with you. As for why, it is likely immaturity paired with difficulty grasping social convention. Or maybe you are (in his mind) the lackey / sidekick who he treats like crap as a mechanism of proving his own coolness. Metaphor: You are Milhouse and his is Bart (in his mind)
Straighten him out, I assume there is a reason the two of you are friends. If that is not an option drop him. Life is complicated enough without people like that in the mix.