You're welcome @sinking

I think you're hard on yourself and don't deserve this self hate, try to think what would you say to someone of your family if they felt like you, I think you would be more gentle if It was someone else that felt like that

It's such a shame It didn't work, I get that it's hurtful because you feel like they don't care about your feelings but your family said that they love you
Even if this event makes you feel like the opposite they cherish you

It was surely hurtful what they said to you in Italian forums, they only saw one negative thing about you and focused on that
But your hate for your brother don't define you, it doesn't change all the good things you did
They don't know what you lived, at your place they would have surely reacted the same

It's a good thing you try to understand you better, it's the first step for recovery
Keep going

It's not because you're borderline, bipolar and so on that you're a psychopath
I have psychosis myself so I understand the weight of the stigma around mental health
But most of us are not dangerous, we're more likely to hurt ourself than others

It's important to express yourself, to get everything out of your chest
But I understand it's sometimes difficult, because hurtful remarks put a toll on you
I already felt like that and was reluctant to say some things
Sometimes to avoid being hurt we can talk to peculiar persons that are more understanding
Talking on mental health forums mostly can be an option