I think everyone can relate to this at some level. I also think there is a base level of discrepancy in the degree to which each person is invested in the relationship. For example, I may give you the feeling that I am your closest friend, but from my perspective you are one of many good friends I have. You may not be my closest friend. Therefore, when life gets busy for me and I pull away it hurts you more than does me.
I also get the ghosting part as I have friends like that too. If a relationship does not bring you joy, then it may be time to let go. Life is too short!