I dont know if its normal but I can tell you that youre not alone. I'm going to be 28 this year and I still feel that way.

that does not always work. for people like my brother, ignoring him makes it worse. Thats very bad advice

I know the feeling. Unfortunately, the only thing you can do is break all ties and get as far away as possible. I am in the same situation and now work with my brother and cant escape. Nothing work...