A child, your inner child – the one that hurts inside – doesn’t want to hear you being rational and calm. “Fuck them” he says and “fuck them for their selfish bullshit that ripped our family apart and ruined mine and my brother’s fucking lives”.
These parents, as wonderful as you need them to be, HURT these two children and left a HOLE, were gone in their lives where they needed adult supervision (think: latch key kids). And this hole in parenting led to another hole – a hole in their heart.
What the parents did could be rationalized all day long but it hurt you very much and look what it did to your brother! They pretty much, through their own selfish needs, screwed up your personalities.
Now, i say all that to make a point: you are both suffering and both need help. YOU CANNOT fix your brother, he has to do it himself and because people learn through example and not through being forced, the only real way to help him is showing him how it is done, how to heal.
Time for you to take the focus off him and start looking inward my friend. You have to save yourself first and then he will follow.