on condition that they love us back, that is not true love. When you add conditions to a relationship, it is an exchange and not necessarily based on Love.
It sounds to me like your friend is looking for approval from others because he does not get approval from himself - he does not love himself. If he does not get immediate approval from others, they do not provide what he values namely approval from other people. He then terminates the relationship and keeps searching approval from the next person.
If your friend ends the relationship because the other person does not deliver the goods (namely approval of your friend), then your friend also saves face. He can then say that he was not rejected, but walked away. In this way he can continue to feel that he is in charge of the situation.
I would suspect that the one thing your friend needs to learn from all these relationships or friendships that he walks away from is that self-love does not come from other people, but from yourself.
Your friend will keep searching for someone who "loves him back", and keep missing the point that nobody can "love him back" unless he loves himself in the first place.
Only when your friend has made that discovery and accepts himself as he is, will he find a person that he can love, regardless of whether they love him or not. He will then discover that many different people love him for who he is, because he himself loves him for who he is. Only when that inner division is healed, will your friend discover that somebody special "loves him back" and reflects his inner healing.
It is possible to have a spiritual awareness, in other words awareness that we are spirit and much more than our bodies, and still have a lot to learn. Being spiritual is about being willing to learn, and not about being better or at a higher level than others.
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