why does god always take away the person we love the most?

he doesn't -- no  gods exist. If anyone here says a god does exist, ask them to prove it.
Then, watch them crap their pants and run home crying to mommy.

God never brings about the evil and suffering we see in the world. Read this article: https://www.jw.org/finder?wtlocale=E&docid=2017012&srcid=share

God has first dibs on all the good ones.

God doesn’t “take” people.  He’s not a killer.

we cannot know why God does this, but we know it is what is best for the person or for us as He never will give us more than we can handle

Someone will ask this same question when you die. It is inevitable. 

Because we were genetically superior to them.

Because he loves you.

Or something.

Because you don't feel as bad or notice as much when a person you don't love gets "taken away"  by which you mean "dies" I suppose and not beamed off the planet or just ghosting you. 

He doesn't always. If He does take away the person/thing you love most in your life, He might be telling you that they cannot give you eternal happiness.
He might be leading you to rely on Him for love and guidance.