You are in a large group of women, 70% of women are only orgasmic in this way. Ways to see if you can explore internal stimulation would involve getting to know your own body/anatomy (the 'g-spot' is between two and three inches inside the front wall of your vagina. Perhaps during other stimulation your husband could try inserting a finger and caress that area (he may notice it is slightly bumpy when you are aroused) by using a 'come hither' motion (i.e. as if he is calling someone over with his finger). You could also try to change position during penetration to get his penis to rub this area - different women find different positions better - check out this site; whilst the person posting the information says things a little different than I would, the information is all there and pretty accurate...http://bettersextips.wordpress.com/2007/05/17/good-positions-for-g-spot-stimulation/