He DID have a right to know and you DID DO the RIGHT thing- so pls don't feel bad. Sometimes people shoot the messenger when they don't like what they're hearing.
Explain why you did what you did but if they don't come around, just forget them and make new friends- as they're not worth it really if this is how they treat you.
You're still young& friends will come and go. So don't stick with people who don't treat you well.