This is a very common story from women—orgasm only through oral sex. You are not alone! And remember only 30 percent of women can even reach orgasm through intercourse. It's not easy and requires lots of communication, pelvic floor strengthening and usually simultaneous clitoral stimulation. You may want to use positions where you can get that clitoral stimulation either through body to body friction or incorporating a vibrator. Experiment on your own with G-spot stimulation and orgasm and then it will be easier to incorporate into lovemaking with your partner. Ultimately I don't think you should fret. An orgasm is an orgasm and it doesn't matter how you get there!