I've known relatively happy couples who've lived out there entire lives where one is an observant Jew and the other is decidedly not. If a couple can agree to to it and is able to communicate well with each other and are able to maintain love and respect for each other, it can work. And if you are already the cook and the "homemaker," you shouldn't have too many problems keeping a kosher home and keeping Shabbat.
It can be difficult though for the one who is observant and difficult for the children to feel entirely comfortable in the community.
My experience, by the way, baring all here, is that my husband and I lived many years years together as strictly observant Jews (I covered my hair, to show you where we were). We became religious together. My husband then lost his faith and couldn't pretend to follow halakhah just for the sake of our marriage. It very nearly broke us up. We have always been a couple who did everything together, and we knew we could not survive as a couple if I continued to believe and follow while he didn't. We tried for a while, and it was an absolute disaster. It was horrible for us, and horrible for our children. So I had to make the decision whether to follow him or divorce him. Our rabbis were no help to me at this time. I suppose they saw what difficult situation I was in and didn't want to interfere? My friends weren't much support either. I think they were freaked out by the whole thing. I felt a little betrayed. The decision took a long time, and we even tried short separations, but in the end I let him convince me to follow him. Perhaps with more support I would have stayed, but I couldn't imagine living as a single mother in that world, with no support (none of my close family is religious). Leaving was really, really difficult. I pretty much lost all my friends and mentors at the same time my entire life changed. I pretty much agree with him and his reasons for leaving now, and I love him very much and only rarely resent him these days, but I do still have some regrets about leaving frumkeit.
Anyway, my point is that it didn't work for us. But I have seen it work for others. If you and your dh do everything together or if your dh is a very skeptical sort of person (as mine is), it might not work. But the fact that even asking about this, makes it sound like it might work for you. And Amy's right. It's not all or nothing.
And Elfie, BTW, I have an internet friend who just moved to Baltimore with almost the same story as you (I really doubt from a few things that you say that you're the same person). If you would like to get in touch with her, PM me your e-mail address, and I'll send it to her.