Brief Answer:
there is need to explore inter personal issues and orgasm difficulties

Detailed Answer:
Hello,
Thanks for using healthcaremagic.

Having masturbation is normal for anybody and can be understood as a mean to satisfy physiological needs. But not having interest in partner generally occurs when there are marital or other conflicts with partner.

In many cases females find it difficult to achieve orgasm with routine intercourse and that could be another reason for doing masturbation in preference to sex.

Before making any judgement you need to discuss with her as she is the best person to speculate reason. Once you talk in normal way with assurance and support she will prefer to tell you the reason which is essential to correct.

I hope this helps you.
If you have more questions feel free to write back to me.
Thanks and regards

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