I'm looking for perspectives and ideas from you all, my PC darlings.

I have this friend...

We've been friends for about 30 years. For as long as I've known her, she has always engaged in one-upmanship (the art or practice of outdoing or keeping one jump ahead of a friend). This ranges from always attempting to "top" every message I send her or every conversation topic we delve into, to her constantly making sure that I know every single time she does something kind or helpful for others.

I believe she is basically good at heart. We generally have a good time when we hang out. I'm just not sure if her one-upmanship is ill-natured (intentionally or not), or if she truly does it out of her own insecurity and lack of self-esteem. (She knows she has issues with both of those, so I'm not just slapping a random label on her).

I try very hard to not let this bother and annoy me. But, many times, it makes me want to disengage with her. She always has to have the last word, and it's usually something that feels like, "I'm funnier, more helpful, and more empathetic than you are." I want to say something to her about it, but she has so many existing self-esteem issues, I know she will take it to heart, deeply. And, she would likely just stop interacting with me altogether.

She tends to be an "all or nothing" person. If someone critiques her in any way, she takes it as a statement by that person that he or she doesn't like her. This makes her withdraw completely for fear of being provided with constructive criticism or positive re-direction. (I know this from situations she's shared with me).

Any experiences you've had that you'd like to share, or any advice, will be much appreciated!