Thee best question ever asked on this forum, and to find your own personal answer, probably a major key to many peoples problems.....Whether relationship, personal growth, depression etc.
I don't have all the answers, and will never pretend to.......Even at 43 I find life is a continual struggle, not so much to understand others but to look within yourself and to remember that realizing that you are loved and loveable...............There's really no starting point or stopping point for that matter..............It's one of those vague life teaching lessons like........
"what's the meaning of life?"...............It's different for everyone and how and when we reach our own level is probably determined by how much thought and experience we put into our own lives.
Each time you feel that you have reached a higher level of understanding you will feel a strong need to find someone who is on the same or higher level...................Instead of asking yourself "who would love me?" or "what right do I have to be loved?"..............Ask yourself, "who am I not to be?" "i am beautiful, talented and intelligent person.
Unfortunately people continually search for that one person or one event in their life that will make them "happy"...............When true happiness is already inside them. :)