Well, I view that matter a bit differently than Ivan Seeking. I'm an atheist - I don't know if there is a god or if there isn't, but I don't see the slightest rational reason to believe in one, hence, atheist - and wouldn't want to be in a relationship with someone religious - be it mildly, moderately or fundamental.
The major faiths are very clear about relationships to non-believers. To believe in the general system, but disregard parts of it someone doesn't like, is irrational to me with respect to the belief system (no matter how irrational or incoherent it is in the first place) and also with respect to the general idea of entertaining coherent beliefs in general. What exactly is the point of being, for example, Christian or Muslim, and then only follow the teachings one likes? You won't go far in science if you only learn the parts you consider fun, no matter how fundamental a part is to the whole idea.
I picture people with faith of that kind as someone who wants their cake and eat it too - don't follow the requirements but still get all the benefits in case there is a higher power. It's simply not logical to me. You can't form a theory based on half of your craft (for example physics), accept that it disagrees with the other half (under the premise that both halfs are well-accepted and proven, required bases for new theories), and still expect to be awarded the Nobel Prize, as an analogy.
I don't expect my partner to hold ideas completely free of contradiction in every little part of their life (though it is a most virtuous task), but the major ones require exactly that. I'm aware that I have no control of who I fall in love with, but I hold my personal view of integrity over fulfillment of romantic desires, and would, as I did in the past so far, not pursue a relationship with a religious (however tolerant) person. I expect the same from a person who falls in love with me - I am but a human among many, and however special or perfect I may seem to a person falling in love with me (or the reverse), I most likely and simply am not that person (talk about love making blind).
I'm perfectly fine with disagreeing with my partner about other opinions and beliefs that are not dogmatic (for example, non-extremist political views).
And though physics doesn't require you to be atheist, in my view it makes religion obsolete for spiritual fulfillment - there's no physical need for a god.
I realize that this position can be viewed as dogmatic, and it most likely is - but I come from a background where religion was a major vector of violence, hatred and death, and I also know myself too well, being a rather sarcastic and often cynical person with too much of an idealist core to not care.
Edit: Just to clarify, I don't condemn relationships between atheists and religious people, either. Everyone has to choose their path, and I don't see anything wrong in being with such a person in the way bad crimes are wrong, or in the way more fundamental religious people see it. I wouldn't forbid it nor try to talk someone out of such a relationship on the single basis of my belief system - I'm just voicing my opinion why I find it wrong from a personal, rational standpoint.
By the way, there are a lot of examples in my own family where there were mostly successfull relationships between believers and non-believers. I would also be ok with the idea if my children chose to be religious (though I wouldn't bring them up as such - I'd tell them the whole truth about religion and its history and would be confident that this is enough to rationalize belief or non-belief).
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nice post!
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