Treehouse

I am a treehouse. You have to climb up to my level if you want to see how I view the world.
I can see everything from the far past to the far future and to the corners of my horizons, but I can't see what's directly below me. I sway in the wind but stay strong. I love being in my tree.
But I want you to come and visit me, climb up to me, for I am lonely. And if you won't come up to me, I can come down to you... but I will retreat back to my sanctuary in my tree just as fast.
When I let you in, it may be small and cramped (don't mind my muse- she lives here), but it's cozy and warm, and I'll let you stay as long as you like. But if you wish to leave, I will kick you out and never let you back in, not looking if you safely climb down or fall into oblivion. For as much as I like company, I love being solitary just as much.