Well maybe your family aren't having proper knowledge and awareness about depression.
Next Steps
Contact and consult a psychiatrist by yourself, ideally with a family member or a close friend who has been in your company often and till recently. They will have been observing you and can tell your Psychiatrist about recent changes in you.
Health Tips
Please don't indulge in Self harming activities, There's hope. there are several effective treatment for Depression. Also you are not alone.