How to tell my parents I want to see a therapist.

Okay so, I'm 15 years old and I have a problem with myself. Back like 2 years ago I had a problem with "narcissism" that I think goes back to my childhood. It wouldn't be that bad if I wasn't praised by people I knew for being a bad person, which only developed with me having problem with empathy and manipulating people, and people treated me like some kinda cool charismatic villain which felt good for me.

Like a half year ago I started too see my bad traits as what they are - bad traits, and decided to get rid of them as soon as I can. With that I started to have a deep fear of people hating me, and I started to not be able to have a conversation without fearing that all my charisma, likeability and self coinfidence is gone with my bad traits, and it's a real pain in the ass for me.

A while ago I started to think if I should seek proffesional help with keeping all my good traits while getting rid of all the bad traits because my personal work doesn't seem to be going nowhere.

The thing is, I don't feel like my parents will let me go see a therapist without me explaining everything to them as they're really nosey. Besides, my brother is seeing a therapist for years now and I'm afraid that me seeing one aswell would make them feel like they failed as parents.

Any tips guys?