I- That's extremely concerning, the people around you that is. I'm hoping this is not real but if it is oof. Don't try changing yourself, faking your personality doesn't work, trust me. If you are a dark person, that's fine, but I suspect not all of your personality is dark. No one is completely dark or light. If you want to prove others wrong and you feel like you want to change, keep your darker parts of your personality, but try to find the light parts, and embrace them. I'm in the opposite situation (minus others, people just think I'm annoying). I have several light parts of my personality, and recently some darker ones have poked through, such as apathy and hatred. I'm not gonna fight them, because I understand their purpose, even though I'm scared of myself, knowing that I can hate someone and not care about them. I have learned not to hide or try to fake my own personality. I embrace both sides of myself, dark and light, and it's honestly less tiring and better for me. I hope you take my advicce.