We don't even call Easter eggs Easter eggs at home, we call them "seasonal spring chocolate eggs" I know I’m missing the point of the thread entirely, but do you give your DC chocolate accompanied by a cheery ‘now don’t eat your seasonal spring chocolate eggs all at once children, or you’ll spoil your dinner’? What’s with the seasonal spring bit? Was chocolate eggs not specific enough? 😁
To actually answer your question, I personally wouldn’t wish a happy Easter to someone if I knew they were of a faith that wasn’t Christian. But I think the real question would be whether or not she said it in thoughtlessness or with malice. I’m assuming there’s no malice or anti semitism in them or you wouldn’t be friends. I think it’s a case of them thinking of you, wanting to wish you well and assuming that you do what the vast majority of the UK do and treat it as a non religious event that involves a bit of chocolate. Which you do, even if you have got a daft name for that chocolate.
I think you handled it in a really lovely way by replying like that and I’d try to think of it as them as thinking of Easter as a chocolate related event that they don’t associate with religion. In fact, I think I’d go as far as to say you’re being a bit of a crap friend by being annoyed with them. If they know you buy your DC eggs at Easter time, and they don’t think of it as a religious event, why would it occur to them that you’d be offended by being wished a happy Easter by someone who probably also only buys eggs? You’re marking the event in the exact same way they do.
If they aren’t messaging you to wish you a happy Passover, or any other important events in the Jewish calendar, then maybe it would be nice to tell them about your life a little bit more. Tell them that your family are celebrating Passover and what it means to you, so that they can wish you a happy x, y, or z and you can do the same when wishing them a happy x, y or z.
Also, I’m happy to be corrected but I believe that name originated from Paganism, not Christianity. I’m pretty sure that the Pagans weren’t celebrating Jesus, so getting the hump because someone wished you a happy Easter instead of a happy long weekend strikes me as being a bit silly.