Hi! This is my first post on Reddit ever, so bear with me if I make any sort of mistake or simply don't understand something. 

To give a bit of background, I was diagnosed with BPD last year after a tumultuous childhood and many dysfunctional romantic relationships. I see my psychiatrist regularly every one or two months as well as a therapist. 
I am making this post before an appointment with a new therapist that has been assigned to me since my old one retired. 

I recently got engaged to the love of my life, and things are going pretty great with my ability to self-regulate a lot better and having an amazing support system. 

However, my concern is that I'll eventually make him a favorite person and destroy the relationship down the line. I didn't always recognize this in prior relationships when the codependency started to seep in, but I'm starting to feel it with him and I'm terrified.

I know having a favorite person isn't the end of the world, but I don't want the codependency portion of it to ruin my life completely. Therefore, I am asking for advice on how to avoid this from happening. I can assume that the first step is to have a conversation with my fiancé about this topic, yet I don't know how to bring it up without him saying something along the lines of, "Honey, that's not going to happen." 

I know this is probably getting into the realm of medical insight so I will leave this as it is. Thank you to anyone in advance who replies and I will take any advice and answer any questions.