Suh-lee-nuh gave me this quote, which I will post, because I love.

Life changes. You get it all lined up just the way you like it and then something beyond your control comes along and bumps you off center. How nice it would be if you could get everything just the way you want it and say, 'Okay, now, stay.' But nothing stays the same. You grow up, make friends, lose friends, go to college, lose track of people, meet new ones, and sometimes you ask yourself why. 
But all I can tell you is the every single experience you go through like this changed you in some way. Every new person who comes into your life changes you. Every moral dilemma or emotional experience you come up against changes you. It`s your job, you decide how.
That`s how character is developed. 

People always leave us... C'est la vie? or God?