I think a few these responses are a little bit prescriptive to be honest and probably reflect either internalised biphobia or a reaction to biphobia.
You know if you have been out as bi the changes are you have had that shite all the time about how we must be gagging for it and can't settle with one person and be monogamous and are only dying to live as part of a polycule and must wear purple and preferably have piercings and die our hair a range of shades... and it's all bollocks...
And yet one thing a lot of bi women have in common is a history of relationships and even current attractions that you can't bring up easily in straight spaces. And there's a lot of stigma attached to being bi and married to a man in particular in some quarters.
Most of my straight "mum friends" talk easily about who they fancy in the media and the like when they're feeling touched out and idly contemplating (jokingly, playfully) an escapist existence. They will talk about their past peppering it with references to people they've been with without a second thought. At work and in playgroups I have often heard peopple say things that demonstrate they're uncomfortable with women who have sex with women. If I was to just talk freely about my attractions it would make a lot of people very, very uncomfortable in my rural Irish town... and there would be a LOT of chatter. It's easy to say these things don't matter but checking yourself all the time can wear you down. It shouldn't be that big a deal to say you find Claire Danes really hot without it being tittered over as something naughty in a way it wouldn't be if it was Brad Pitt. I don't notice that I need to say I fancy Claire Danes. I notice that I check myself from saying things in certain places that make it obvious that I am not straight.
And you know if you have had previous relationships with women, the chances are at some point in your life you will have experienced what it is like to be stigmatised for your sexuality in a way that hasn't been experienced by many straight women.
I actually find a conventional heterosexual lifestyle incredibly stifling. Not the actual sex. Not the raising of kids. Not the having a partner. But the fact that in most places I go giving away any details of my history would ultimately cause me to be deeply judged, mistrusted and spoken about in ways I really don't care to be spoken about. And I have a bi married friend who is out in some of these places and I am not, and so I have heard first hand the BILE that is spouted about her being out - her looking for attention, probably seeking a threesome, probably being unstable. I kid you not.
My bisexuality has been enormously relevant to my parenting because I had PND and I was bloody petrified that I would "give the gay away" (*caveat = yes, I'm not gay) and this would impact on my psychiatric diagnosis if they knew I had a history of childhood sexual abuse. So that's one reason it's been very relevant to me in my marriage and as a parent. It was a really big factor in me not getting the right mental health help when I needed it because actually female sexuality is HUGELY stigmatised in psychiatric services, and bisexuality particularly so. This is a reason why there are FAR higher rates of mental difficulty in the bisexual population than in lesbian and gay male cohorts. This is also relevant for PND.
And yes, I do quite often fancy other women. A lot. I think about them, a lot. And I am happily married to a gorgeous man that I fancy a lot and have absolutely NO intention of cheating on ever - and I still felt really thrown off earlier this year to have one particular attraction... though I knew I would never act on it etc. I have not found when I have been attracted to other men that I have found it to be so ungrounding because ultimately I can have sex with a man anytime I want and I actually do find sex with men and women different. Shoot me.
I am lucky to be with a man who is not fetishisizing or difficult about my sexuality (and I wish I didn't see this as luck but it is really not that easy for so many women) and I am particularly grateful to be with a man who is also happy for me to be involved with LGBT groups "even though" I am SHOCK HORROR married to a man which apparently makes my whole sexual identity entirely irrelevant...
Listen, I don't give a shiny shit how anyone chooses to navigate their own sexual identity but it does piss me off when people suggest that it is "irrelevant". Mind your own experience. Don't dismiss some people's need or desire to find connection about any particular aspect of their experience, be it their sexual orientation, penchant for bell-ringing or love of fine red wine. We all need a bit of connection about the things that matter to us for whatever reason and wanting that does not mean you have some terrible problem with your partner or aren't happily married. That's just biphobic bullshit.