well for starters there is basically no association between increased violence and psychosis so get that out of your head...the only time I've ever seen increased violence and psychosis together is when there is concomitant drug use at least in the literature

second is it any wonder he chose to keep this a secret since you immediately associate this with violence? Personally I tell people within a month but I'm stable and on meds and I'm sure his issue is that he went off meds, he'll probably be fine once he starts again so stick it out