Thanks Hidden Warrior.
For point 1) love usually helps define who someone is... Sometimes we don't know who we are..Love makes us do some strange things right?If we know who we are, we would already know what we are capable of doing. One must at least have a general idea of themselves before that person can love another. If that person doesn't, he/she will be molded into something by the person they love. On most occasions it is usually something that the person doesn't fit into.
2) how love brings a sense of security... Well love should be a shelter where you can feel safe when you need comfort. I meant this in a broad way. Yes people do argue. If one cannot communicate with the person they love, then the relationship cannot flourish, since it will become lopsided. love should make a person feel good{ this is a broad overview}, there will be days, that won't go your way, that is a part of real life. The reason why this security cannot be absolute is that if it were, there would be nothing to look forward to, or work for.
3) ever changing... In order for love to survive it must adapt to the changing needs of the relationship. That is why the people with the best relationships are constantly advancing while the basic concept of loving this person remains the same, the "how" I love this person constantly changes to keep up with how someone needs to be loved.
Does this makes sense, it is quite confusing. I am not implying that you take this at face value, but to keep it a corner of your mind, along with what everyone else has posted, written or told you, and then come up with what makes you feel the ebst.