Help I need directions

Not sure if this is the right place to describe my life but im 23 years old I feel like im degrading my life instead of making it better my mind is all over the place one day ill wake up in a good mood and positive thoughts next day ill feel worthless even though i did the same things i did the day i woke up in a positive mindset i just don’t know what life wants from me. My mom asked me if i needed therapy because my life hasn’t progressed after my older brother died 8 years ago i feel like I don’t need a therapist I honestly don’t know i miss him dearly im the only child now my mom and i moved away from our home town and moved down south with my stepdad I’ve never felt so alone in my life my stepdad rarely talks to me my moms rarely says hey when she comes home from work she barely sees me even though we’re in the same house. I think i just need to disappear nobody would even care my mom would cry but at the end of the day she will go to work and her life will continue just like how when my brother died I need help I don’t even know why im on here saying this ive read other peoples situations and they seem alright with not existing want to be someone in this life or whats the point of living if you can’t actually feel alive I don’t know what im looking for with this but I decided instead of a journal I’ll just write my thoughts on here Reddit is like a older brother to me I read and just read maybe that’s the problem idk