I don't think she wants to humiliate me, and I don't want to be humiliated. But I find the idea of her sleeping with other men due to my performance to be inherently humiliating.
Not to be intrusive, but I am curious-- what's wrong with your "performance" (how I hate that word), exactly?
lack of erection
inability to maintain an erection
premature ejaculation
inability to orgasm
micro-penis
Or is it something else, like lack of good bedroom skills in general?
Have you had other partners in the past who left you for not being a good lover?
I'm sure you're aware that good sex shouldn't only focus on the penis. There are so many ways to share sex that don't involve putting penis in vagina! Have you worked on your "outercourse" skills? Have you become the world's best pussy eater, or finger-banger? Most women don't cum from intercourse anyway, but need clitoral stimulation by other means. Many women can cum from breast stimulation. Toys also come in handy. You can wear a penis extender, or a strap-on, or just use a vibrator or nice big dildo on her.
Are there any kinks you share, any other kinds of sensual play you've tried, like massage, light impact play, simple bondage, reading erotica together, etc., etc.?
I don't know. Maybe you've tried all these things, and she still insists she's unfulfilled, and wants a man with a different kind of penis.
Personally, being pansexual and non-binary myself, I have been with with cis men, with transwomen, with cis women, with non-binary people, etc., and we've done sex in all kinds of ways, that may or may not have involved insertables.
I have been with cis men who couldn't get hard, but could still cum; or who could get hard, but couldn't cum. I admit, we enjoyed kink activities as well as "sex."
The only time I was really unfulfilled was when I had one experience with a guy with a micro-penis who had absolutely no oral or fingering skills, didn't kiss me, or fondle my breasts, nothing. He wanted oral from me, and to get his tiny penis into my vagina, and to cum, and that was it. HE was a one and done, believe me!
I don't want another woman sexually besides her, and she has already stated she wouldn't want me to try that. I can't handle the one I have. lol
Anyway, besides our sexual troubles, we have a great, loving relationship. A large part of me is okay with her finding what she needs. I don't really blame her. She's unsatisfied. I just don't want to feel inferior because of it, at the same time, I guess...
Have you
tried to satisfy her? What is wrong?
Have you and she had therapy, maybe sex therapy, read any books or articles, worked on other options besides opening up to her having other lovers?
Introducing new lovers for her opens up a whole Pandora's box. She might fall in love with a sex partner (i.e., polyamory, the point of this forum). Then what?