I am a M(19). I have two brothers; (17)M and (21)M, our cousin also loves with us; (24)M. So now what happened; My elder brother and my cousin have been making dark joke on me for past 2 weeks like; How many D!ka can I suck or shove up my as, and some similar things. At first it was good, I also laughed with them but at some point they started to cross the line. I asked them to stop but they never did, we had several fights over it but things never got physical. But yesterday or more specifically, today, after 12.20 Am, we had another fight. They said that as it's my birthday, I might take more than I usually do. They were referring to that dark joke and I didn't like it. I asked them to stop but they didn't and things got a bit physical. For context, I have never hit my elder brother in life so yeah it was a big thing. My mother was in their support saying that what I did is wrong, they were just joking and I shouldn't overreact. I know that I shouldn't have punched him but they had crossed the line. My dad supports me saying that they shouldn't say something like this to their younger brother, especially infront of parents and what I did, though too far, was correct. Currently no one except for my father talks to me in my house, I am completely isolated. So tell me, AITAH for hitting my brother over a joke?