"But what about him??"

That's a question we all ask at one time or another:
Why did this happen to me?  Or its converse, "What about him?"  I've asked the question many times myself.
You've asked it, too:
"How come she got promoted?" or..."Why can't I find love? All my friends can."  or, "How come she got sick? Everyone around her is healthy, and she lives healthier than anyone else I know." Or, "Why am I better off than the janitor?"
Some of the things that happen to us are the consequences of what we do, and we can trace those out.  In other situations, it's very puzzling and hurtful, and leads us to jealousy and sorrow--or a sense of invincibility ("I make my own luck!") and entitlement. None of these emotions gives a true answer, and sometimes we just don't know why certain things happen.
But the question always comes up, because we truly want to know what makes our life worse, or better, or different, from the those of other people. What makes me different from someone else--someone successful, or beautiful, or privileged, or sick, or broke, or homeless?
Peter asked the same question in John 21:21-22:
"What shall this man do?" In other words, "What about him?"
And the answer he got back from Jesus was classic:
(Paraphrasing now): "Don't worry about him. He's mine, and I'll direct his life the way I see fit.  As for you, Peter, follow Me." 

Nothing in life is more important than this principle.  
If I keep my eyes on HIM, and follow Him, then I will be fulfilling my own very personal destiny.  My destiny is not Peter's, or Bill's, or Jane's, or Sammy's.  My destiny comes from a path laid out before time began by the Lord Himself.
So does yours.  And this is wonderful.  There will be a time when all the successes of life mean nothing.  All the money you earned, the home you lived in, the children you have, it will all mean nothing, because in eternity, all those things will be over.  All that will matter is how you followed Him.  That's it.  Nothing else.
That's what Peter found out.  His life was to be different from John's (John 21:21-22, again), but it didn't matter:  the only issue:  "Follow Me!" You want life to be right?  Jesus has a couple of words for you:  "Follow Me!" You want to realize all the potential in your life? "Follow Me!" You want to have all the things God wants to give you? "Follow Me!"  You want Him to smile on your life? "Follow Me!"
Our problems almost all come from looking at other people, rather than at Him, and finding what He wants, and then going with it.  If we do that, everything else falls into place.
Of course, what you'll ask now is, "How do I do that?" And the answer is fourfold:
1. Listen for Him.  You'll know when God is speaking to you.  He can talk as loudly as you need Him.
2. Do "the next thing."  Most often, a course or direction in life just seems natural.  It agrees with us, with our own plans, with what we want, and that is almost always the right way to go.  If you're a younger person, and you've always wanted to be a forensic scientist, do it.  If you're and older person and you've always wanted to finish school, then go for it.  If you're a boy or girl, and it's time to get up for school, do that. Your dreams are often His direction.
3.  If you get serious messages of redirection, LISTEN to Him and for Him.  My own greatest failings and my own worst decisions have come when I did not listen to "redirecting messages," and went a direction that seemed dictated by circumstance or by pressure from others, when I knew better.
4.  Whatever you do, set your course to follow Him. You cannot go wrong if you follow Him.  Life will be it's best, and eternity will, too.