If you love something...

This saying has been on my mind lately;  If you love something then let it go.  If it was yours it will come back to you....unless you rip its wings off and break its heart.
I made up the last part.
Unless said thing is a boomerang, is it going to come back for sure?  I guess a youngin would...while they are still young and have needs to be met by only you.  Maybe not when they are teenagers and adults with money and wheels.   Actually, I hope my girl grows up and flies away, but comes back to visit and hang out, b/c I've taught her to be free and independent.  I would want her to come back on her own free will if she wanted.
What about when accidents happen? What about when loved ones go off to fight wars?  Maybe it's not about physically letting go...
Dogs will usually return to you if they are fetching a ball you are throwing.  Cats return usually when food is to be had.  Kids and men too I guess.  Men will also return for a different sort of nourishment...

Do living things only "come back" to us because we are meeting their needs?  What if someone else is meeting their needs?  What if they are meeting their own needs?  Or wants?  Or desires?  How can you purposefully let the one you love go, for the chance of someone else to love them and meet their needs, better than you can?  Should you?  Surely that's insane.  Wouldn't it be more insane not to know?
I could ramble forever on this but the real question is...is anything really ever ours to have and own?  Maybe for a moment yes.  For a lifetime?  For more than a lifetime?  Will we be reunited with them after this lifetime?  What about tortured souls that are neither here nor there?
How can we own love?  Is the only pure test to let it go?  This sounds so ridiculous.  I guess we can't own love, we can only share it.
I'm glad this is out of my hands.