Trying how to explain why you feel a certain way, has be the single most biggest soul search one would have to delve in. There are so many layers of why on top of why. But in the end does it even really matter?
As long as it makes you happy and that one void in your heart seems to be filled every time you're with that person or maybe that pain you get from smiling so hard while texting doesn't even phase you. Why does there have to be a reason on why you want that person. If they know how you feel and it's reciprocated that's all that should matter. Most of the time we fall for someone and don't even realize how deep we are until we start to see them slipping from our grasps, and then it's when you see that part of you that made you so complete. You'll do anything to keep ahold of that. People always say if they chose to leave they never cared about you to being with. But that's what's wrong with us nowadays, no one wants to fight for anything and expect it to be so natural.
Sometimes that's what people need to see to stick around ... That you care.