Friends That Don't Listen Aren't Worth Keeping — No Matter How Long You've Known Them
If all they can do is talk about themselves and their problems without ever listening to you, dump them.
Knowing someone for a long time does not mean that you are obligated to continue being friends with that person throughout your entire life. We all grow as people and we can grow apart. The idea that you have to continue being friends with someone just because you've known them since high school is a PERFECT example of the sunk cost fallacy. You've already "lost" the time being friends with them in the first place, so if you no longer vibe the same way you did, don't stay because of all the time you've already invested in the relationship.
In reality, relationships and friendships are incredibly complex and we all have different standards for friendship.
However, listening is one of the BARE MINIMUM friendship standards for most people. After all, we get to know the people in our lives through conversation, so if we aren't listening, we're only in the friendship to talk about ourselves. That isn't fair to either party involved. People deserve to have close friends that actually listen to them and care about what they have to say.
Sometimes, people play you. They seem to be a good listener for a while, but as your friendship progresses, they slowly start only talking about themselves. Once, I had this friend who was so obsessed with talking about herself that she would interrupt me just to talk about herself. It got to the point where I could hardly get a word in. But if I did manage to talk about myself for a minute or two, she wouldn't remember a single thing I said. Why would I ever want to continue being friends with someone like that?
I don't think people understand that being a good listener requires quite a bit of emotional energy. It is absolutely exhausting to listen to someone else talk about themselves and their problems all the time, without any reciprocity. We all have problems and if you're truly my friend, you care about my problems as much as I care about yours. Being a good friend and a good listener is a two-way street.
My point is that bad listeners make bad friends. I should not have to teach someone how to be a good listener and a good friend and you should not have to either. So, if all your friend can do is talk about themselves and their problems without ever listening to you, dump them. They truly aren't worth your time or emotional energy.