"Toxic" friendships and boundaries.
You are her idol. This type of fascination I used to observe as a child, Master popularity would have 2 or 3 followers that copied the gold even one's every action. They even walked like him. Such enablers even get involved in serious crimes if the golden one suggests it.
I think your partner is right, to break off contact because- you'll never reduce the intensity, it's all or nothing with that type of person.
If you did suggest more boundaries you are likely to suffer backlash.
Finally, these people often resent the golden partner. For your partner is closer to you than them.
My wife of 10 years had a best friend. When my wife and I got engaged my wife showed her the engagement ring. Her friend said "that's cheap and nasty...If I was engaged to you I'd get a proper ring". Alarm bells went off. It didn't last long after that.
I don't think your relationship with your friend is a relaxing one hence unhealthy.
thanks so much for writing your post and starting this thread and discussion.
A friend was emailing a friend overseas and she had met the friend. So apart from one meeting all the communication was by email. The friend overseas would complain my friend would not email often enough even though she emailed over Ten times a day.. she would. O plain if my friend wrote Dear .. or said take care and lots of other words she didn’t like.
my friend would complain to me how stressed she felt but kept emailing as her pen pal had many mental health issues. My friend liked her own pal and they had fun times and supported each other for years until something happened and the penpal stopped. communication for a week so my friend decided it was time to stop.
my friend realised how much stress she had been under but still worried about her pen pal.
I know it is different in real life but she realised enough was enough.
Only you know how much you can cope with and what will work for you.