Has anyone here ever been the "favorite person"?

I came across this recently and it explains a lot of what I went through. She used to say I was her favorite person. Out of everyone she's been romantic with she would always choose me. All of this kind of unprompted stuff I didn't fully understand outside of face value.

Id respond: "Ok. You're my favorite person too." Or "I would hope youd choose me...??"

The first one flies right under the radar. Why wouldn't you be in a relationship with your favorite person.

The second one doesn't make any real sense to me at all. Why even bring up past romances, rank them, and then put me at the top as if I'd be happy about it instead of just weirded out?

I was the love of her life one moment and she wants me out of it the next. Until that subsides and I'm back to being the greatest. Always leaving or threatening to leave. Always trying to fix it and come back. Sometimes multiple times in the same week. Goes from love bombing to degradation on a dime. It's all black and white thinking. Always the extremes and nothing in the middle. ​

​Has anyone else ever been the favorite person before? What happened when you left?