SO SORRY about the TMI that is about to follow but I could really do with some advice. Longtime lurker/poster but namechanged for obvious reasons.
DP and I are early 30s, have been together for 6 years, no DC. Sex life mostly OK, bit thin on the ground but we do both work ridiculous hours and value sleep more than almost anything else, to be frank.
As the familiar story goes, when we first started seeing each other the sex was great, lots of variety and give and take. I thought I'd hit the jackpot as previous boyfriends were stingy with anything other than PIV sex. Then it trailed off a bit and I got less and less despite giving the same-ish as before. I asked why, he said it hurt his tongue if he did it for ages. OK, but even a couple of minutes would be nice, no need to staple your tongue to my clit for an hour 
Over the years I have asked him to do it more often, he will once or twice, then forget all about it again for months until I work up the courage to ask again. This makes me feel like such a sex pest. I find it humiliating to keep asking and then keep getting ignored. Consequently it has been about a year since any sort of Australian kisses.
I don't know if I am being too sensitive and should just pipe up or demand oral sex - but that feels so aggressive which is so not me and to be honest I just want to feel wanted. I don't want to ask, I want him to want to make me feel good.
Has anyone got any words of wisdom or been in this situation and made it work? 