A conversation and all human communications require more than just one single person talking. It's a two party exchange of giving and receiving. If one party is obsessed with only incessant "I or Me" topics and hardly ever pauses to take an occasional breath, it becomes a discourse of self-absorbed hedonistic over glorification, and the other person (s) might just tune out, elect to walk away, or hang up the phone.
These sybaritic talkers may merely find their dog, or house cat and bore them with their narcissistic prattle.
If their critters wish to eat they are obliged to at least appear to be listening. The rest of us have no such obligation.
We have all known people like this, friends or maybe even family members. The older I get the less inclined I am to endure these people or those occasions.