Hello—
Looking for advice on how to explain this. Basically
1. My(28) girlfriend (26) knows I’m bisexual (but hetero-romantic). She’s also dated/experimented with women.
Good, you've started with honesty. This is something that's super critical, and is something that cannot be rebuilt once it's been shattered. You get the opportunity to do it once and that's it. It seems to me that chose correctly.
2. We are in a closed relationship and pending a conversation otherwise that might stay that way.
Is this what you both want? Have you talked about the differences between love and sex? Have you explored jealousy and passion as serious topics. It is not uncommon in most relationships for physical intimacy to wane after a period of time. It will come back, but you will both have to work at it. Failure to do that work, or differences in rate the desire for physical intimacy declines or returns can lead to significant problems.
3. I love her enormously and want to build a life with her. I also want to continue being super honest with her.
Make sure that these aren't just pretty words. Love can be hard, but honesty can be even harder.
4. I am also deeply sexually attracted to men (as well as women) and love non emotional sex with men and women.
This is a touch concept for those have not explored the differences between sex and love, or who have self-esteem issues, body image issues, or any combination of those things plus anything else that may be applicable. I am in a way the opposite of you, I'm homo-romantic but can be deeply sexually attracted to women, but I don't have "emotional sex" with women.
Most of the guys I have dated have really struggled with that. I don't believe it's a gender thing, it's a "human thing". People might like to know where they stand, and it's uncomfortable when you can't draw a neat box around yourself that indicates where the boundaries are.
My gf has a preconception, grounded in some personal experience and anecdote that men who are “bisexual” are one step closer to just wanting to only date men. I am hoping to explain to her that 1.) I love her 2.) my attraction to men is purely carnal (I love the thought of fcking the occasional twink and gagging on cock, So arrest me) and I couldn’t imagine long term relationships with men. I am with her wholly.
You've kind of given yourself a blueprint for the work you need to do.
Both of you need to explore that preconception, and the things that led to it. This is also going to involve exploring trust, sexuality, and likely self-image. Those are dangerous places for many people. You could find things that will end your relationship, but you could also find things that will strengthen more than you could imagine. Just keep you head about you, and understand the risks you take. That said, you will never gain anything if you don't risk something.
With respect to your love for your girlfriend, explaining is not going to be enough, you're going to have to live your explanation. But she's got to trust your actions, your explanation, and you, and you need to know where the boundaries are. You both do.
Any advice from guys who’ve had similar experiences? I really want to stress that there’s no chance of me ever leaving her for a man, I just love dudes for the fun of it.
If you're in a monogamous relationship with your girlfriend you may have to give up on sex with men. She's not male, and if you're being honest with her and with yourself, you can't go straying and expect her to understand or be happy about it. Having been in the opposite situation (committed relationship with a guy), we both agreed that our relationship was closed and that neither of us was going to stray, in any direction. However, we both acknowledged that we both still masturbated, and that it was perfectly OK for us to explore kinks that the other didn't share through porn and sex toys. It was further agreed that if it started to feel like it was going to go beyond that sort of thing it had to be talked about, lest there be real and lasting damage.
It wasn't perfect, but it did work pretty damned well.
