He is more of a sociopath than a psychopath, with the way he treats others and his view on the world I have no idea how you are going to develop him as a character.
Dude I don't want to insult you or anything but I think this fanfic has a severe blow to its quality from him being revealed as a psychopath more so tan the earliest chapters decrease in chapters meanings and length his constant rambling on more than one occasions with little to no reason his inability to handle situation better and you my friend make everything happens according to mc will and plan this .any be tolerated during the war by saying they are more distracted but after it all eyes will neon him just like danzo but with the difference of having no council to back him up and with tsunade desertion his action will have no backing the third is more of a neutral party that's very much swayed by the action of others if he wanted immortality that much simple train master the five elements recreate the old anime techniques chidori rasengan kirin the yin yang elements increase his chakra reserve and the control to max when he feel confident enough just go to the moon get DNA samples of toneri then use it to rather inject himself with it to make him pseudo otsutsuki to gaing higher life span wait for orochi betrayal then sneak on him acquire his reincarnation technique then move his soul to a new body made of toneri DNA until the battle at the valley of the end then when tobi appears you can drag him to another place by battle until zetsu get in to save him then acquire some zetsu DNA make a new body tat can get the mc to be perfectly healthier aka don't reject him each three years ten apply orochi technique voila you did get perfect body immortal has the five elements
if I am not mistaken for you to attain immortality in the world of naruto .. you have to eat the fruit of the chakra .. or be the juubi jinchuriki .. because the juubi is a mass of vitality then it is practically immortal ... will you do this?
So because he is loyal to his first family, he won't even try to make friends? The family part I can kinda understand but why can't he still try to make friends ?
Psychopath are those that dont understand emotion while sociopath (which is him) are those that understand it but konda forsaked/gave up or ignores it, like Orochimaru
He is convincing himself from telling all that crap and after rebirth your parents changes and new parents should be more important to you that is present if not than you are just living in past and you can't make your impression and Future here in the present condition. So try to forget past and live in present because who gives birth to you, you get their flesh and their spririt as well but in small amount. So your mother here have more right on you than your past mother or father.
Sekz