Feeling lost in transition

Hello, throwaway account here. Looking for wisdom from the wider community here - I'm unsure if anyone in my life would be able to understand my situation without judging and unsure where else to turn tbqh.

My partner (32F) of 3 years and I (35M) have been exploring opening up our relationship recently and it has gone pretty terribly from my perspective. This has been something she has been pushing for about a year and we have gone from threeways, to swinging and recently attempted to fully open - which sort of blew up in our faces.

I have been fighting her the entire way tbqh - this was never something I saw myself doing and initially felt it was not compatible with my long term wants in a relationship and a life. When we tried out group scenarios, I was very surprised at how much I enjoyed it. I felt so close and connected to my partner in ways that I never expected - and in many ways the intimacy here was deeper than anything I had felt with her before.

I was very very against an open relationship - but after a year of bringing it up and some positive signal in group scenarios I agreed. It's something my partner deeply wanted, and I do feel like she believes it's something I would also really enjoy if I truly gave it a chance.

Our experiment didn't go very well from my perspective. I had a hard time attracting partners that I was interested in. I read a bit of Polysecure recently - which went into this a bit, and this is apparently something that straight men struggle with when transitioning. I am very used to having a lot of success in dating very easily - and this experience was sort of shattering my perception of myself a bit. My partner was not dealing with this same issue, and I was not handling this imbalance very well.

When I would go on dates - I felt that they were a bit pointless. I remember being out a few times, sort of just wishing I was at home hanging out with my partner. It made me feel very upset knowing that they did not feel the same way when they would go out on dates.

Ultimately though, I feel like the biggest issue was that we as a couple did not feel like we had the tools to deal with these feelings. My partner would withhold information about dates she was particularly excited about - which made me feel like she was hiding deeper feelings for certain people. I felt (maybe irrationally) that our relationship was losing all of it's stability - from my perspective we were rushing into this so fast and her opinions on what she wanted from this kept changing week over week - and I felt (and still feel) very unsure about where things will go next. There have been multiple times where she has (very subtly) stepped over a boundary that we had set - and though I do trust her I also feel like deep down I was always worried that she would do it again.

When I would go to her about these feelings, I would feel a lot of resentment from her - and she would communicate that she felt like I was doing this just to hold her back. That if I had found someone exciting for me - that I would be ok with everything and I just need to keep pushing forward and deal with these negative feelings. I felt a lack of support and understanding here, and ultimately this caused me to spiral and for us to close the relationship back up. She also communicated to me during these conversations that going back to a monogamous relationship long term is no longer on the table for her - and if we can't find a path forward here we should likely go our separate ways.

Generally - I do think she has a point that this may be something that, if we were properly prepared to deal with, I would deeply enjoy. She still holds a lot of resentment towards me - but we're working together on a plan.

The plan:
- I continue personal therapy and figure out if opening up is something that I actually want to do. If I decide that it's something I'm only doing to appease her - we likely won't try again. Ultimately i think this looks like us going our separate ways.
- We start couples therapy to address the issues in our relationship that came up when we tried this. Ultimately I feel like I need to rebuild a bit of the trust, emotional safety and security that were lost as part of this experiment.
- She also goes back to therapy. She recently started anxiety medication for the first time in her life after pretty severe battles with anxiety and depression - and we both feel like post medication she has felt emboldened to make the changes she has always wanted. She is going to explore this and a bunch more along the way.
- We re-evaluate after a few months, and maybe try again, maybe break up, maybe try to find some other compromise? I'm really unsure

Generally.... does this seem reasonable? I really have no idea what to do from this point. Please help lol. Any perspective here from more experienced folks would help me a lot.