Delayed Ejaculation

[Dav1d]

I have delayed ejaculation, I am not able to ejaculate during sexual intercouse, just when masturbating. If I spend 3 or 4 weeks of sexual abstinence I can ejaculate during intercouse. I am 39 years old, with really few relationships, during years only masturbating. I have never take drugs, medicine, I enjoy good health.

I read this in the wikipedia, and I think it could be the cause:

"One of the main causes of delayed ejaculation is adaptation to a certain masturbatory technique. The sensations a man feels when masturbating may bear little resemblance to the sensations he experiences during intercourse. Factors such as pressure, angle and grip during masturbation can make for an experience so different from sex with a partner that the ability to ejaculate is reduced or eliminated."

What can I do ? Which treatment I need ? Is there a easy solution for me ?