I(31F)feel unheard by my older partner(57M) after a threesome—am I asking too much?

TL;DR:
I’m 31F (intersex) dating a 57M; after a threesome where I felt left out, I told him I wanted more balanced attention. He called me “dramatic,” reminded me we’re not in a relationship, and only replied with a thumbs-up. I’m okay with casual but still want respect, how do i proceed?

Hi Reddit, I’m a 31-year-old (F/intersex) currently transitioning back to living as a woman (long story, I was transitioned to male at 13 without my consent). A few months ago, I started seeing a 57-year-old man. Initially it was a hookup, but he told me he was interested in something long-term. Since then, we’ve had an on-off dynamic—I’m sometimes invited to threesomes with him and another woman, and he’s also mentioned wanting to marry this other woman who’s based in another city.

Recently, I joined him and a woman (this is another woman)for a threesome. While it was mostly fun, I ended up feeling left out at times—he kissed her way more than he kissed me, and I felt like the “extra.” Later, when I tried to gently tell him I felt a bit objectified and wanted more balanced affection next time, he basically said I was bringing “drama.” He also reminded me that we’re “not in a relationship,” which felt dismissive. He told me I'm his submissive and my feelings are not relevent.

To be clear, I’m not asking for exclusivity. I just wanted him to understand I have feelings too, and that I’d appreciate some acknowledgment if I feel neglected. I texted him politely later to say I wasn’t criticizing him; I was just being honest about my experience. He replied with a thumbs-up emoji and didn’t engage with me further.

Right now, I feel really stuck and unheard. I’m normally open-minded, and I don’t mind sharing him or having a casual setup as long as everyone’s on board. But I also want my feelings taken seriously. I’m worried this pattern of dismissiveness will keep repeating, where I give more than I get in return.

Has anyone been in a similar situation where they want a casual or semi-open dynamic, but still need basic respect and emotional acknowledgment? How did you handle it?

Questions:

Am I being “dramatic” by wanting more balanced attention and a little empathy?

How can I set boundaries or communicate better without him dismissing me as clingy?

At what point do I walk away if I keep feeling undervalued?

Thanks for any insight or advice you can offer. I’d appreciate hearing from others who’ve navigated multiple-partner or casual situations but still maintained respect for everyone’s feelings.