My wife is Jewish. She's so Jewish her last name is the Jewish equivalent of "Christ". But she's Jewish only by heritage. But it's a strong heritage. Her grandma and grandpa fled both the Germans who were rapidly advancing into Russia and the Pogroms by hiding in the Ural Mountains, and they lost two kids in the process.
It's a strange culture for people who are not familiar - that of keeping heritage and tradition but not religion. If you ask anyone in her family what they believe happens when you die, they'd likely say you just get buried, and people move on. For them, there's not much else beyond what is purely real and tangible.
My wife is a bit more spiritual than that, having gone to and enjoyed a Jewish school when in Russia (though it was more out of de facto segregation and safety in numbers than because her parents wanted her to learn about their traditions). In fact, when she began to really, REALLY enjoy Jewish culture and history and traditions, her parents took her out for fear that she was becoming inundated. She still tells me stories about how she came home wanting to have a traditional Seder (the meal celebrating the beginning of Passover), her parents said no, and she was incredibly disappointed.
But with that suppression of the inundation of religion, it was interesting that her family inundated her with the belief that she needed to only marry another Jew. The way it was explained to me was: non-Jews will marry you, and then many years later when things get tough in the marriage, they will turn on you, spit on you and call you a "kike".
She also told me stories about how the Jewish school she was a part of would put on parades and marches through the city, and all the children would dread them. Non-Jews (mostly Orthodox Christians) would line the sidewalks of the parades and pelt them with rocks as they walked down the street, and when the children complained, the school simply said that they were trying to "raise awareness" of the Jewish presence and by simply doing that, the other children would stop throwing stones at them.
So I can imagine how difficult it was for them to move to a different country with those fears of anti-Semitic sentiment, and how they likely wanted their daughter to seek out another Jew for the same reasons they put their daughter in Jewish school - de facto segregation and safety in numbers.
So when she brought me home, tattoos, piercings and all, I can't imagine her parents were too happy. But for so called "spiritual" Americans, it's different. I was raised Lutheran, but probably because my family moved around constantly, we never really had a church we constantly went to, and religion was never high on our priority list. We celebrated with family on the holidays, and religion was rarely brought into even the most religious of celebrations. So, like I said, for "spiritual" Americans, obviously not the devout, saying you're Jewish or Christian, or any other religion, (except, unfortunately Islam - it's sad, but that's different now-a-days) is like saying you grew up in Michigan or Idaho. Different, yes - but it serves as more of an interesting conversation topic than a dividing wedge between two people.
My wife asked me if I wanted to convert. And I considered it for a while - but seeing as how neither one of us really subscribed to religion as a major pillar of our lives, I thought it would be a little disrespectful and blasphemous to convert just to get married to someone, and then never follow through. So we both said, screw it - and forever after we were ALMOST as happy as this: