Friends that you had to let go.

We have all had friends that eventually got too much to take.

Over the last several years, I have noticed something about people that has affected how much I am willing to tolerate.
SOME people talk about themselves too damned much.
To me, the most interesting person is the one that engages others in conversations. The dialog is a shared one and isn't one sided.
The absolute worst is the guy that only talks about what HE is interested in.
I went here, I went there, I bought this, I sold that.....
I know some guys that are great though. They ask questions, talk about tech, family stuff, current events and don't make every subject revolve around themselves.
TWO separate terminal bachelors that I've known always talk about themselves and show almost no interest in what anyone else wants to say.
Why is that? I know it isn't limited to just bachelors but I wonder if a lifetime of NOT having a woman around to care for tends to render them completely selfish.
Every car show that I go to, I see guys that I haven't seen in several months if not a year. Some are considerate people. Many are not. I always try to remember their car and ask them about it. Some reciprocate. Some see my question as an excuse to give a 17 minute monolog about everything on their minds. These are the ones that are slowly being added to the list of people I don't care to speak with that much.
I've mentioned this issue to many people that I know and some have said they feel the same way.
Tim is a guy that I've known for more than 12 years. He used to live in town but moved away for a job. He calls and wants to talk about everything HE is interested in. When I try to elaborate on something from my own day, I get the obvious signs of disinterest, followed by Okay, I gotta get going.
The last time he did this, in closing, I said...."Well, it was great listening to everything that YOU wanted to talk about".
He was surprised....What do you mean by that??
The guy was clueless. He is a software engineer but not smart enough to take a hint on this.
I like having friends but if the ones I have only see me as someone to listen to THEM talk all the time, I'll quit taking their calls.
How about you?
Have you had buddies with bad habits you just couldn't take?