Hi hope610. I'm a bipolar guy and also go through hypersexual episodes so perhaps I can give some guy insight and what can possibly help your boyfriend to stay faithful going forward during your relationship?

I realise everyone is different and my bipolar condition might not be as severe as your boyfriend's but I find a personal value system drawn from my own personal philosophy helps restrain me from getting up to nonsense. At the time of my last relationship my partner and I also had a binding relationship promise/oath that I took very seriously. Our relationship itself ended because of natural personality differences, not because of any cheating.

I also found that consciously trying to not allow myself to be put in risky situations that could lead to cheating was also helpful, as when there's limited opportunity then the possible challenge to one's manic desires is almost nil.