Hi all-

I (26F) was in a 10 year monogamous on-again-off-again relationship with my partner (26, transfem), I'll call her Daisy. Starting in August this year, she 'realized' that she needed to be polyamorous after a romantic interest cuddled with her on a bench. She gave me an ultimatum that either I'm ok with it or we break up. I'm defending my thesis in December and I cannot deal with losing her right now, so I decided to try as hard as I can to be ok with it.

That being said, she expects me to be willing to hear about every sexual and physical thing she does with people, and it's killing me. I feel really upset and nauseous, and I wish it wasn't happening. Her time with people sounds fucked up and it triggers me to hear about. One of her recent really intense relationships involves a trans man that regularly sexually assaults her and pushes her boundaries, and she puts up with it because she doesn't want to lose the relationship. I hate hearing about that person, she texts him constantly when I want to spend time with her, and I feel like I'm drowning.

Recently, I've been trying to establish some boundaries: that I don't want to hear about her sexual time with people and I don't want to argue about why polyamory is better than monogamy. I'm doing what I can to stay in my lane, live my own life, and try to process the new relationship paradigm as much as I can to try to reduce horrible feelings of sex repulsion, jealousy, and possessiveness. Daisy responds to my boundaries by comparing me to homophobic people, saying I'm rejecting a huge part of her and not supporting her as much as I should.

I feel really upset and stuck. I don't have the emotional energy or time right now to read books on polyamory, have conversations I need to have, even explore any other relationships, etc. My day-to-day is filled with teaching, studying, writing my thesis, going to meetings, and drowning in conflict with my Daisy (who has been unemployed for like 6 months and fills her time with new people). I feel abandoned and unappreciated- I offer her so much kindness and support generally, and she's been filling most of her time with other people who treat her much worse than how I treat her but she overlooks all of it because she gets all her self esteem from the validation that others give her. I barely see her anymore and when I'm with her, I drown in hearing about other people or repeatedly asking her to not text her partners when I'm with her.

I feel like I can't just leave her or not talk to her anymore right now. And she won't agree to any boundaries I try to set. I've wanted her to not have sex with people in the bed that we use together. I've asked her to not text partners when I want to be present with her. I've asked her to not discuss her sexual exploits, or plans to have sex with others, with me on days I don't feel good. None of it is respected.

I have a personal therapist, I've been expanding my social network as much as time will allow, and I've been working through a dialectical behavioral therapy workbook to try to manage my difficult feelings that are getting in the way of functioning. Any advice is appreciated.

Side note, I suspect she has BPD and she has a really intense trigger response if I even suggest she's done something wrong, so that makes negotiations or even talking about my feelings with her impossible. We tried couples therapy for a few months but we had brutal fights afterwards every single time that effected my schoolwork so we had to discontinue. (She was mad that the therapist agreed with me too much and made her feel like she was doing things wrong.)