This is a tough one. I don't feel there is any one person that I could imagine never having in my life.
I could put a picture of these two who created my life:
Or a picture of this girl who makes me sparkle:
Or a picture of these guys who teach me about love every minute of the day:
Or a picture of any of the countless number of people in my life that I don't want to ever not have in my life.
This would be an easier challenge (oxymoron!) if it was posting pictures of people you wish had never been in your life -- the toxic ex, the "friend" who had used you, the kid who bullied you.