Hi Summer_Twilight,
Some guys aren't the sentimental type and don't like sending cards, except maybe when they're dating to impress their girlfriend. "It's too much work to send a card," is a normal thing for a man to say. Many men are happy to let their wives handle the card writing responsibilities.
... But I will add this. It was rude of that guy to say such a thing to you, because you had taken the time, trouble, and thoughtful kindness to send a card. He should have said a simple "thank you."
Also, there are in fact many people who won't be your friend, or who will be a friend but act weird around you, (well yeah, that's not much of a friend though) based on your religious beliefs or lack of belief. No, it's not nice, but that's how the world is.
Me, I believe what I believe and if someone tells me they don't like it, it's their problem.
In any case, I think it was very kind of you to send a card.
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