My first wife used a dildo on me several times, and I loved it. We talked vaguely about having another couple join us, but both agreed it couldn't be anyone within our circle of friends. Unfortunately, the internet was pretty new at that time, so searching would be difficult. She vacillated between kinky, and rather disinterested in sex. I could never figure the cause.
I used to get a lot of bi support from a Domme girlfriend. She would tell me to strip down in front of her and "tell all" about my encounters with men, until I started to get visibly aroused. That exercise always culminated with her instructing me exactly when to bring myself to orgasm while she, fully clothed, casually observed. She wanted to know every detail about my sex life with men (including actual encounters and fantasies), but she never revealed anything about hers. This state of imbalance and vulnerability was extremely arousing. She would occasionally reward me by letting me enter her sweet body and sleep with her afterwards. I fell deeply and permanently in love with her. That remains long after she ended our relationship. That's how deeply she reached into my psyche. I continue to think of her during and after each intimate encounter with a man. She taught me to embrace my bisexuality completely.
With my long-term girlfriend, the "encouragement" was indirect and not her intention. When we first hooked up, I felt that I needed to come clean with my extensive experience with guys before we had sex for the first time. Surprising to me, she fully accepted my history, but fully expected monogamy. I'm also one to never cheat. But she broke up with me many times during our relationship, and during those periods she fucked other guys, but I only did extensive masturbation to gay porn and writing about my gay fantasies and experiences online--a major turn on for me. But when she found out about all of the online gay stuff, she didn't like it at all, even though we were on a break and she was dating other guys during those times. I guess it was more the morality aspect of porn. But she always came crawling back to me, and my gay feelings were gone again when we were together again. But how she treated me in the relationship, and the rollercoaster nature of it, and all the breakups, kept pushing me more and more towards my gay desires. But then she also began introducing some light bondage and discipline into our sex lives, and eventually started fucking me with a strap-on dildo, probably because she knew that that was a gay fantasy of mine (though I'm still a bottom virgin to this day with men). But she really loved the power feelings it gave her with the B&D and pegging me. But her fucking me in the ass with her strap-on always--every single time--made me feel how much I wished it was a real man fucking me with his real cock. Again, her actions were strongly feeding my gay desires. And she ended up really wanting and loving being fucked in the ass with my cock. Every single time I fucked her anally she had an orgasm (overall she was always multi-orgasmic every time we had sex anyway). I really loved fucking her in the ass, partly because with her pussy I always had to use a condom because she wasn't on the pill, but with her ass I could go bareback, and cum inside her. I love that so much. But I think subconsciously it was again feeding my gay desires (since I have fucked guys in the ass and loved it as the best sex ever). And then when our relationship really became bad in the last few months, and she just wanted to be friends with benefits (while she dated other guys), for the first time I began doing the online gay stuff while we were still "together". And in the end, I wasn't able to orgasm while fucking her vaginally without thinking it was a guy that I was fucking. Going to a gay place in my head while fucking her gave me the necessary excitement level to be able to cum. She as a woman, and especially as the particular person she was, wasn't doing for me anymore. After I finally broke up with her, I had no remaining desire whatsoever to ever want to have a sexual let alone romantic relationship with a woman again (though I still find some of them very sexually attractive), and I have that feeling to this day, 4 years later. I was so excited to be able to finally go all out with gay sex (unfortunately 2 months later the pandemic hit). I don't want to say that she turned me gay, because I think I've mostly been gay my whole life, though suppressing that part of me all along. But she did indirectly encourage me to live my gay truth. Now I live as a fully gay man, and I'm so happy and proud.
This is a very interesting account of what took place with your orgasmic response pattern with women and men. In my situation, after I parted from my Domme partner, my next and current girlfriend is a highly orgasmic and loving woman who was raised as a radical Catholic, someone who truly tries to emulate Christ. This mixture of spirituality and eroticism has kept me firmly in the pan-sexual realm of orgasmic response. She simply gets off on having me vaginally fuck her regularly, so much so that it maintains my own orgasmic response with women. She vocalizes and communicates with profound body language during sex, which helps us to synchronize our orgasms. She loves maintaining penetration after those thunderous and synchronized orgasms and being held close, just like my best male and non-binary lovers. In a sense, she is non-binary, because she also embraces both her feminine and masculine characteristics, just as I do. That's really the key to being pansexual-- embracing both the masculine and feminine aspects of your psyche. Casting those rigid binary assignments aside has been my path to feeling like a whole person and relating to other non-binaries.
She sounds like an extraordinary woman! How fortunate you both are, together. Synchronicity with a lover is everything.
One girlfriend who used to blow me multiple times a day was great encouragement to blow other men. I shared my youthful experience of blowing my friend when we were young and several days later she shared that she can't suck enough cock with just one man. She took me to an adult bookstore where she shared her kink with me in a video booth and together we sucked a lot of guys for over a year and a half in those booths. It was great to suck with her knowing we both loved doing it for pleasure, nothing emotional. We had one friend that we shared at home but he stopped coming by after he got married. That was a great situauion, coming home to find him there with her sometimes, other times her coming home to find me on my knees for him.