Why do we choose to love people who don't appreciate us?

They don't seem to notice what you're doing for them, and instead they complain and take advantage of you, and complain more. You would get upset, and you may hate them for what they did, but you will never stop loving them.
How funny that the arguments we have could be so pointless, and not worthy, yet we still waste our breath, time and effort to participate in those endless bickering.
More often than not, love hurts. It gives us false hopes, making us hope that they might one day understand and appreciate whatever that you did for them. But some people will never understand.
Or maybe, sometimes they will realize that they have been an ass. Then they will apologize and plead for forgiveness. But like the nitrogen cycle, or the Krebs cycle or whatever cycles, the same thing will happen again, and they will hurt you again and again.

then you will begin feeling lost because you don't know what to do next, to leave or hold on. but you'll choose to hold on anyway because love always give false hopes.