You can get a strong erection while watching pornography. You can masturbate without difficulty. But when you are with your partner, the erection becomes weak, disappears halfway through sex, or sometimes does not happen at all. Then the questions start: "Why does it work alone but not with her?" "Am I losing my sexual ability?" "Is something wrong with my testosterone?" "Have I watched too much porn?" "Why can a screen turn me on when my partner can't?" This situation can be