Milk is sweet on its own so therefore it can always choose to be alone, but it realizes that it can be beneficial to others(coffee) who had a not so tasteful life when it is solo, and joins them to create a beautiful taste out of what didn't initially have the capacity to possess beauty on its own... The fact that you find yourself where you are today, probably fulfilling your dreams, or taking a ride in your choicest cars, or spending on the best qualities in life, means like Milk you have the potential to sweeten another bitter life, and bring out the best in it. Help someone today!