Rlyss

I wouldn't joke about it if I were you mate. I've had way too many problems in the past about that and even though I've accepted that it'll never happen, I still joke about it in the hope that it might, and she takes it too seriously.

Lots of people might chip in here and ask if she was sexually abused as a child, that seems to be a big question these days, but your answer will probably be more along the lines of 'Some women think it's degrading, some think it's dirty, some believe there's no point when they've got a vagina to do that, and some just won't do it, that's final.'

Logic won't work on her, and if by some magical mystical chance that it did, you'll know that she's not doing it because she wants to, and while head is head, head from someone you know is enjoying it is a million times better, right? She won't be convinced it's clean, playing the 'it's only fair' card won't work because she'll probably tell you that you don't have to go down on her anymore, and since most guys love doing it, you lose that way too. She won't give you a reason, she's just refusing. (Personally I think that's bullshit, but that's just me, I'd do anything for someone I loved, but then again I don't think there's anything wrong with oral sex.)

Personally I think the bottom line is that she's never going to do this for you, and it sounds like you can live with that, and with her, so your only choice is to suck it down, because she won't.

Edit: I just re-read this and I'm worried it has a really menacing tone, but it's not supposed to at all. It's supposed to more more light-hearted but in my experience if she says no, then it's no, and I've never been given a real reason other than those I've mentioned.