The life-long friend who nonetheless annoys you

I have a very old and close friend whose personality and behaviors can really exasperate me at times. I don’t want to end the relationship - we are in our 70s and have been friends since our teens. She’s very different from me - very dramatic - at times histrionic, never married, never had to live or care for another, subsequently quite self-centered. Whatever happens to me inevitably gets turned around so it’s all about her. Even if she’s sad on my behalf, it becomes all about how she is sad. She knew my late DH longer than I did yet never came to see him or me during his long illness because she “just can’t” do that kind of thing. I’ve had to do so many difficult and heartbreaking things because I had no choice so I don’t have a lot of patience for that while I recognize it can be a personality trait she can’t change. I’ve put distance between us by moving away after DH’s death - and had to hear how terribly sad that made her - but of course we are still in regular contact. This is like having a sibling who is challenging to you while not really toxic - and I’m an only child so struggle with how to deal so I don’t get agitated. Advice?