First of all, although it’s actually very common for women not to achieve an orgasm through vaginal penetration alone, it is fairly uncommon for a woman of her age to never have had an orgasm. So right off the bat I’m thinking this doesn’t have anything to do with what you are or aren’t doing during sex and, instead, it might be a medical problem.
The fact that your girlfriend says she has “discomfort” sometimes during sex is a clue. Sex shouldn’t be uncomfortable. If there’s any kind of pain, that’s going to be a turn-off, certainly, and it’s a sign that something’s not right. She might not be lubricating enough or there might be some kind of subtle anatomical abnormality going on.
So, first thing, she needs to see her doctor and have a complete medical exam to rule out any physical causes.
If everything seems fine, then you’ll need to consider psychological issues. You said she hasn’t had any sexual trauma, but you might want to talk more about that. If she was scared or had some kind of bad experience the first time she had sex she may associate sex with those feelings, which may get in the way of her ability to climax.
If there’s no medical or psychological issue going on it could be simply that she’s never experimented enough with pleasuring herself to know how to reach an orgasm by stimulating her clitoris. Believe it or not, some women don’t really know how to masturbate by stimulating their clitoris.
So maybe some experimentation is in order here. If she’s shy about masturbating then you could encourage her to try different ways of stimulating herself when she’s alone. Maybe she could use some lubrication or a vibrator. But if she’s open to it, you could help her discover what turns her on. And I’m not talking about intercourse here—that’s the last step because roughly 40% to 50% of women can’t orgasm from penetration alone.
I think you need to sit down and talk more about all of this with her. Encourage her to see a doctor for a check-up. And try not to get too heavy about all of it. If it’s true that she really has never had an orgasm, then you could be the one to help her discover this—which would be a pretty incredible thing for both of you.
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