My gf has trouble having orgasms - never had one

So, my gf seems to not be able to get orgasms. I go down on her, and she tells me it starts feeling really good, and then it goes from feeling really go and climaxing to being sore immediately, without any sort of orgasm or closure. Any suggestions on what could be wrong? She's never had an orgasm before, and it sucks when you can't please your girl. Could it be something I'm doing wrong?

And I've told her to try masturbating but she just doesn't seem interested at all in doing that. So it's up to me!

Are u fingering her while u are going down?

Maybe involve other foreplay, like breast fondling, fingering, etc. Take it a bit slower perhaps.

well first off all try more foreplay, build her up more, thats always a god one for woman. then once your going down on her put a finger or two inside her and curl it upwards so that your pressing against the wall of her vagina, then press and rub there but dont be to rough unless she asks for it, see how that goes