Here's my fav quote on love by Neil Strauss:
“We have this idea that love is supposed to last forever. But love isn't like that. It's a free-flowing energy that comes and goes when it pleases. Sometimes, it stays for life; other times it stays for a second, a day, a month or a year. So don't fear love when it comes simply because it makes you vulnerable. But don't be surprised when it leaves either. Just be glad you had the opportunity to experience it.”
Smart manipulating energy that is. If you to expand the concept of love you will be surprised to find that we are designed with some built in triggers. These triggers get activated by age, environment, and other factors. The closest you can get to understand it, is when you become a parent and watch how your love take off on an auto and uncontrolled rocket traveling between the past, present and future, an between your mom/dad, wife/husband and your baby/children. I think you will get to realize that there is some “manipulating power” behind the veil that is trying to insure the continuation of life no matter what and whether you like it or not.