I get it we lied to our SOs. . . but please

[MatildaJ.]

When I met my wife I thought...My crossdressing is a highly personal weird thing that I do on occasion and doesn't bear mentioning.

Exactly. Suppose a wife picks her nose every morning and secretly eats the boogers. It's gross, but it's not harming anyone, and I can see why she might want to keep that secret. Or suppose she exchanges letters once a year with an ex-boyfriend, but they never meet up. Or suppose she fantasizes about her dad while she's in bed with her husband. It's fine with me if she wants to keep that fantasy a secret.

as we began building a life together...[I felt I should] share this "weird habit that I originally thought didn't bear mentioning!"

Indeed. Once you have the desire to share the secret and to feel accepted by your partner, or you want your partner to participate, or you want your partner to give you more time for your secret hobby, then you have to find a good way to tell them. But as long as it's a very minor part of your life, I don't feel it's a moral imperative to reveal everything.

If this is something you do once or twice every six months? One where you're spending less than most people spend on coffee over the course of the year? No, I don't agree that you "must" disclose.

That makes sense to me.