Marc,

I've said it before and I'll say it again.
Boys are totally dependent on their parents. If you want to have an enduring relationship with a boy you must establish a connection to the parents. Otherwise if they move away, you WILL loose contact. But if you are a family friend you have a reason to keep contact.

Boys are hardly capable of organising a long distance relationship. Only adults can do that.

If you have time before he moves, try and connect with his mother. Make a way to keep in touch.

Otherwise you have two choices, move on and (whilst not forgetting him) learn to live without him
or
give up and die.

Your call on that one dude.

Blessings
Cat.