Best friend ambushed me with my fiancee's ex girlfriend and I dont know how to even process

Throw-a-way account as my real one is tied to my business.

So my best friend stayed over my home for two weeks while her apartment is being repaired from a major pipe burst. My fiancee is amazing and does well enough that he's offered me to quit my job and focus on growing my Yoga studio. He does the majority of the cooking and is thankfully a neat freak, so a lot of the housework is shared. She took notice of this and maybe its just me but it felt like a shift in the vibe when he made a special dinner for us.

The following week she just shoehorned back-handed compliments where she would say things like " Wow I didn't realize how much thinness and beauty can take a girl" . She's always been indifferent to him but that has been her stance with any guy I've dated. This time it was a but more annoying to deal with. I attributed it to her frustration with men and her current career along with other things she's confided to me and I let it slide.

Flash forward a month later (last weekend) she invites me to a brunch date and tells me its important. I see her and another woman at the table with solemn faces. My bf explains to me this is my fiancees ex and wants me to know the truth about him. They had (supposedly) met at their workplace and figured out the connection when she posted a group picture online. I'm sitting there floored and I just felt like this was stuff that happens in reality shows.

She tells me about how lazy he was and how she pretty much foot the bill for everything outside of rent. She mentioned she constantly caught him watching porn and he kept promising to propose but never did until she kicked him out. I sat silently for a minute and asked when this all happened, and she mentioned this was 8 years ago. I felt everything at once; empathetic but also betrayed by not getting a heads up, vulnerable but mainly confused. I explained to both of them his story when we met , outside of watching porn, matched what she said. He told me he got into fitness, dropped a ton of weight and got IT certifications when he felt like he hit rock-bottom. He blamed some of his former laziness on sleep-apnea. He said he never followed through with anything and wanted to change that. They were not happy with that response at all.

My bf was now incensed and asked me if I could look inward as to why I want to marry him. She was telling me how I would owe him thinness for the rest of my life and how men do not change. That my "comfy" life is a way to control me. I've never felt this way about him at all , He's shown me how he manages personal savings and encourages me to do the same in my personal accounts. There was a year I couldn't work out due to a car accident and he never mentioned my weight gain at all( also the time I knew I wanted to marry him). I mentioned all this and asked them what it was the outcome they wanted. My bf stood up frustrated and chuckled that "Im just not getting it" they both left despite me repeating my question.

I sent a text asking her what that all was about and her response a day later was essentially by selfishly not holding him accountable I was ' making shit worse for other women...goodbye". I'm still so confused by all this and need some outside perspective.