It sounds like paranoia and maybe psychosis. However, those things are not only ascribable to Bipolar (which I have). They can come with many other mental illnesses. He definitely needs a psych evalaution. If he sees a psychiatrist and gets a diagnosis, even a prelimminary one (it can take a lot of time and effort for a psychiatrist to get a correct diagnosis, let alone the right medicstions) and starts on meds there one critical thing. He MUST seee a therapist and start going through psychotherpay - it is critical that along with medication comes psychotherpy. I wasn't told this for YEARS and was only receiving therapy from the psychiatrists I saw and some of them are good therapists, some not (mainly not in my experience). So seeing a therapist/psychologist is critical.

At the same time as all this - your own mental health is at stake. He may never do any of what I just suggested - you cannot make him. The severe nature of what he is saying to you could be having an impact on your own mental health and you seeing a therapist yourself could be a really good idea.