I have been with my boyfriend for three years and we have been sexually active, but he has trouble ejaculating. we can have sex for about 2 hours or more but he still won't ejaculate. in one point of our relationship i thought it was me but he told me that with his pass 3 girlfriends he never ejaculated with them either. when he masterbate he is able to ejaculate. so i was wondering could you tell me what the problem could be?