Oh, hun, I know that path all too well! For three decades I lived with them blaming me for being 'dramatic' and 'twisting the situation to my benefit'. I wasn't really allowed to have an opinion because it might go against something or they may not like it. When I finally began to stand up for myself, the amount of rotten things I was called was absurd. I won't go into all the details, because I don't want to detract from what you are going through, but let's just say things were very bad. My point is, I can relate to what you are going through.
Your opinions mean a lot! They are what make you the person you are, they are part of you. Don't let anyone try to take them from you or play them down as unimportant or 'worthless'. Your opinions are anything but worthless!
You would be surprised by the strength you actually possess. I have thought the same thing going through all this: that I don't know how much longer I can keep on going. But all this is only a single moment in your life. This will all pass in time - I know it seems like a long time from now, given you are almost 16, but hold on!! I thought the same thing at your age (and, no, I cannot believe I just said that, because part of me still feels like that terrified, miserable, lonely 16 year old!) Find something to immerse yourself in, something to take your mind from the pain and hurt. Something you can use as a mental escape point when things escalate. (For me, since I was 6 miles from nowhere, it was books, music, and riding my bike.)
It's hard to get people to see your side when your parent is narcissistic. Narcissists use a technique called 'gaslighting' to project the issues as being your fault, or that whatever they are really doing, you are causing it to happen. (ie: in recent events, I was accused of being so upset I was shaking, screaming and red in the face. In reality, I was the calm one and it was the other person projecting their actions as being mine. Does that make sense?) Find a way to get the social worker to see the truth. I know that isn't easy, or may not be possible given the situation and/or time frame. Are there any other relatives who have witnessed your parent(s)/sibling's actions or would have cause to see your side of events? Are there any other adults (teachers, school aides, clergy, family friends, etc) who you could turn to for help? Find any and all resources you can. Do an internet search for domestic violence/abuse aids in your area. Unfortunately, I know these things all take time and you feel like time is not in your favor. But keep your chin held high and know that you are better than all this crap. You are a beautiful person who deserves to be happy just like anyone else. You can do this!!!
I'm really new to Reddit, but if you need to vent/cry/just have an open ear to listen, I would be more than happy to lend you my shoulder.
Stay strong! <3