<human>: My partner has been completely faithful to me during out dating relationship (14 months), so I don't have any hesitancy that she is going to remain so. Two years ago, my partner (who is not bi-sexual) fell into a massively co-dependent relationship with her best friend (who deals heavily with same sex attraction). This led to them having an on/off physical relationship which ended about a year before my partner and I started dating. 

I know that my partner has moved on and has no desire to fall back into temptation of ever being physical or being too close to her best friend again, but while my partner still lives with her best friend (along with other roommates), and while I know the best friend has moved on as well, I must shamefully admit that I cannot fully trust the best friend. I often think that if the best friend was out of the picture, I would not have to fight the memory of their past. My partner always tells me it will better show the power of forgiveness if she and her best friend can remain in each other's community and lives. While it took me a little while, I can understand this side of it, but there is a strong tension in my flesh not trusting the best friend, but wanting to as she is dear to my love and me.

I just needed to process, be challenged, and hear the advice of non-biased parties. Are they playing with fire? Is it wrong for me to want the best friend out of the picture? Is it a red flag that my girlfriend's first reaction is to defend their relationship and not try to make sure I'm comfortable, but calls out my hesitancies and insecurities? Are they wrong? I suppose anytime you aren't pursuing love for someone, you're wrong.

The bottom line is, I want to pursue health in this. I don't want to dismiss my feelings. I want this to all be healthy. I want proper boundaries.

Can you condense the text into a few key points?
<bot>: A while ago, my partner had a co-dependent/physical relationship with her best friend and they still live together/hang out. I'm having a hard time knowing what's acceptable/if my feelings are insane or justified.