when is it time to just give up and accept it?

So i have noticed, alot of people just dont know when you stop, take a step back, realise things that have nothing to do with them, actually none of there buisness at all and just accept it and move on. Not many people can do this at all, weather it be siblings prying into there younger siblings relationships, 'friends' having to put there unwanted opinions in every problem you have, or even a stranger on the street walking up to you and they tell you what your doing isnt right. Everyone seems to do it. (I think even i do it sometimes)

So seriously when is it time to just give up and accept whats going on around you? In my opinion, unless someone is getting beaten up, or murdered in front of your eyes, when it comes to peoples personal lives, relationship and all of there buisness, in the end its not up to anyone else but them.

They may choose to move state, write a book, delete there facebook, not use there facebook, ignore your phone call, turn there phone off completely, just walk past you in public, say hi to you and nothing more, not invite you to there birthday, stay home on there birthday, not tell you where they live ect... The list goes on.

They have there reasons and its not up to you to tell them that they are making a mistake, or what there doing is wrong. If you can sit there and say that then you oviously dont actually care like you say you do.. you cant cant mind your own buisness and accept the fact its not your life, you have your own life, they are off doing there own things and if its more interesting and better than what your doing, suck it up, dont be jelouse, and concentrate on making your life fun and exciting instead of sitting on facebook complaining to a bunch of people who dont actually give a shit but pretend to because they too have nothing better to do but hear about how shit other people think there lives are sitting at the computer all day reading the same status over and over again waiting for someone to pretend to care.