Is it when you always be by the side of the person or is it when you keep talking to that person or sitting near that person and holding that persons hand. No, I don't think so you realize it very much. You come to know how much you love/miss a person and how much that person loves you, only when, even if you are physically thousand of miles apart, you stay close to each other by heart. Thats what is true love. You really really miss that person, you feel as though you are all alone, lost completely out of the world.
You keeping thinking of that person each and every second, whatever you do, wherever you go. You keep talking to that person monotonously, not over the phone or internet, but through your inner heart; the heart which shares love and affection. You keep murmuring that persons name within yourself throughout the day/night. You keep waiting to call that person and talk for even a few seconds and those few seconds feel like long hours talk. You keep expecting a mail from that person, first thing early in the morning and even a single "Hi" from that person makes your day at work happy and fresh. You keep watching time and waiting for that person to come online however late it is for you in the night, and chat for a few minutes happily. Always you keep praying Almighty God for that person's well-being and ensure that person is safe, happy.
You keep staring at the latest photo that person sent you for a longgg time, without even realizing that its late for you to goto bed. You keep saying to people near you that you want to go back as soon as possible. You desperately want to see and hug that person and spent much time with him/her. You tend to shed a few tears when you are alone and keep thinking of that person. You keep looking for things to get for that person when you go back home. In fact the toughest of all is, though you got all facilities like reaching through mail, phone or meeting in person is possible, you tend to avoid just thinking he/she would be busy. That would accumulate a lot of pain in the heart.. In spite of having work, you tend to spare time to compose a nice mail to that person, expecting that person to enjoy reading the contents and give a cute and sweet smile .hhmmm.....
Now you realize how much you are crazy and how much you truly madly and deeply love that person....!!!