it is better to come out in a safe environment, they could try to harm you so please be sure of yourself and be ready to accept the consequences, if you really trust them then go ahead
its your decision, but I'd say don't cause it could risk a lot of things, like your family Turning on you, and tbh, no matter how many times they say they love you, it doesn't mean they do. love is something you have to show, not just say. if they say they love you, but constantly shame you for being bi, do they really love you for you, or do they ......
Should I tell them???