Hi:
I want to talk about an unwritten social rule.
I know that when a friend is no longer interested, they can ghost you. Even when you attempt to tell them about a special occasion or some accomplishment or life event, they are not obligated to acknowledge it. I get they are not interested but I feel it's kind of rude not to acknowledge the situation.
For example,
This friend, who I had a brother-sister friendship to for many year but ever since he moved to another part of town and joined a church where he met all kinds of new friends. Since then, he has seemed to outgrow our friendship. I attempted to tell him about a recent life event in my life but at no time he has ignored my friends and I.