i have a brother who was sexually abused when he was 13 years old.he is now 25 and only upon being faced with a marriage proposition has he disclosed this horrific violation to us. he is afraid that due to the assault he is now impotent. he told us that whilst he was resting at a friends place, he had a n erection and this friend on noticing it, suddenly and violently grabbed his erect penis and began pulling it very severely causing him immense pain.he says that after that encounter he felt as though something was "disconnected" and he has seen a gradual decline in maintaining an erection. for too long now he has suffered mentally and emotionally and now feels he will never be able to satisfy a woman. please offer me any sound advice as to what we can do to help him or what necessary steps should be taken in order to conclude if any physical damage has been made and also how he can deal with this mental torture he suffers daily.thank you