You should encourage him to seek counseling and support him, if he’s willing to go for help. That’s the best you can do in this situation. You are not his therapist and cannot do any more than offer your love and support. His problems can be effectively treated by a mental health professional in counseling.
Apparently he views masculinity in terms of aggressiveness and dominance. Angry men who feel weak and who feel that they have something to prove, can sometimes be violent. These men also tend to be jealous and controlling in relationships. These characteristics might not describe your boyfriend, but his aggressiveness towards men and his need to prove his masculinity could translate into aggressiveness towards you.
It’s a mistake to think that his violent tendencies towards men are an isolated issue. Your stating that he has not harmed a woman and you do not think that he would means to me that the issue has at least crossed your mind. His anger and need to prove his masculinity, could be problematic for your relationship and could lead to you being harmed.
If he’s unwilling to seek help despite these issues, then you have to decide if you want to stay in a relationship with someone who knowingly has problems but refuses to treat them. Remember that the purpose of dating is to find the best match and that most of the people you date will not be a match. I would advise against choosing a mate with evident psychological problems who is unwilling to deal with them. They make for disastrous life partners. Please take care.
Dr. Kristina Randle