I'd recommend e-mailing--I've done that in the past first for difficult topics.

Do you think it would be easier or more difficult to talk about it with your H there? Like, does he know you're punishing yourself with it? If he doesn't know, might be easier to talk to T about with just the two of you first. Otherwise, you'd have to deal with both of their reactions at once. I say this as someone who is also in marriage counseling, as well as individual therapy (though with different T's). MC allows me to e-mail, so sometimes I would tell him about something in advance before bringing it up in session, which made it easier.

I find it very difficult to talk about sexual topics with MC, who is male and for whom I have some paternal transference. I find staring at the carpet while talking about it helps! It's also difficult to talk about with my female T though, so I think it's just a difficult topic in general because it's so personal.