first off, we arn't having sex, i am talking about oral sex (sometimes with fingering). however, i have read many guides and had lots of input but it is to no avail - i have only gotten her to orgasm once with her help. and it took hours.. literally. now, before i even touch her down there, there is tons of foreplay. she is already very very wet and shoves my head down there. in addition, we've been together a while and are very comfortable with each other - we communicate very well. she's told me what feels good, suggestions on what to do, we've slept together naked, masturbated infront of each other. however, i still can't get her to orgasm (again). i am a pretty coordinated guy with lots of endurance and can do the same thing for long periods of time, soft or hard. even doing this for hours has not so good results - even though she gets so wet that she drips. she has said that it feels good to the initial touch, like the first lick, but then her body gets used to it and it becomes insensitive. when i mix it up, it feels a little different, sometiems good, but the same thing happens. if i go too much or too hard, it hurts. again i've read several guides, used fingers, tongues, combinations of both, come hither, alphabet, vacuum, long licks, etc, all at different tempos and strengths. all with teasing her LOADS(kissing her everywhere, kissing from the knee up to her vagina but skipping over it). she is EXTREMELY horny before i touch her vagina. now, when she masturbates, she puts on her panties. this is even after she is very very wet, including her clit, and is naked anyway. in addition, she usually takes 15 minutes+ (going on to an hour even sometimes) to get off just herself. and well she said it has been getting boring, even with me doing various things to her while she masturbates. i'm the first person that she has let do these kinds of things to her, i've done it to one other person before and she was really easy to get off. what can either of us do to remedy this problem?