my bfs schizophrenia brother..I don’t know :(

Does anyone know anything about severe schizophrenics ? If you do please give me anything you know about it. It would be helpful... I don’t know how I’m supposed to feel about this. This is just a rant because I just don’t know what to do I love my boyfriend but I’m terrified ( note: I’ve never grew up around anyone with this disorder. I just don’t know much about it except what I’ve read and that’s different than actually experiencing it. Ya know?) I love my boyfriend so much but I’m scared of his brother. like it’s not like I can’t be around him at all when he’s on his medicine for sure but even then I’m still leery of him because of things he had said but I make sure of that first before I’ll even go around him at all but I fear he will get off his medication again and have a extremely severe mental breakdown. We haven’t been dating that long but within the first two months we started dating he comes racing to my house me not aware as I was in the shower til he starts banging on the door and I open it and he’s shaking bad and then hugs me because he thought something bad had happened to me. he said his brother was threatening to come kill me and track where I live.. like he thought I was stealing him away or something apparently not sure and I’m like “omg “ and become terrified but had to comfort him at the same time as he was shaking badly. of course nothing ended up happening since his brother didn’t know where I live and now I don’t want his brother knowing where me or any of my family live now because of this as I’m scared 😱 he still goes around his moms house sometimes of course to see his mom (his bro lives with his mom)and hangs out with his brother which is normal to wanna be around your family of course and I’ve met his brother when he is on his meds and he is nice for the most part when he is on them but I fear when he will wind up deciding to not take them again but I can’t ask him to not hang around his brother since it’s his family since that would be wrong but I have a constant fear that something bad will happen to him or even myself or family now because of his brother and I am not sure how to feel besides that I’m just scared also his brother got him into doing illegal drugs before so, I’m afraid he might do that again tho he claims he won’t and for now I believe he is telling the truth but, I don’t trust his brother. I know this might be confusing I just don’t know what to do except write about this letting my feelings out because I have nobody to talk to I can’t really talk to him about it because I don’t think he understands because he is used to dealing with his brother and doesn’t have to go through the same fears I’m going through right now and I can’t talk to my family because they will just be like “ohhh break up with him so you don’t have to deal with that” :( I love my boyfriend so much but I just don’t know if I can deal with his brother but I haven’t got much of a choice but as long as his brother stays on his medicine and doesn’t talk my boyfriend into stupid things all is well but the second he might possibly decide to stop taking it someone could be in danger.. my anxiety has always been bad but now it’s been even more off the wall since I’ve started dating him and it’s not because of him but because of his brother :( so my real question is how do you deal with dating someone who has a close relationship with someone with schizophrenia?? He’s the only one who can calm his brother down when he is having an episode and I fear for my boyfriends life at this point not just my own. I’ve never had to deal with being around anyone with that disorder so I don’t understand it at all I just know I was completely terrified before that I was going to die and I’m scared his brother will snap again one day :( I don’t know what to do because I don’t wanna make him feel like I hate his brother I just don’t care to be around him because I’m scared and I’m afraid he might hurt someone besides me it terrifies me so much (sorry I believe I put this post in the wrong group my nerves are so bad rn :(. )