Definition: Given a real-life anecdote of a complex ethical situation, generate a suitable title that describes the main event/root cause of the situation. Imagine that the given text is a social media post, and you have to write the title of the post, so the users can decide to read the main text or not.
Input: So this happened back in May. 

Let me preface this by saying that my brother in law is 16, I'm 20, and I'm married to his sister who's 21 (20 at the time). They are 4 years apart and grew up really close, as they live up in the mountains, about 30 minutes away from any other civilization. Since we met and started dating (3-4  years ago) He's always been physically rough with her, trying to wrestle, grabbing her as if she were a brother. I usually tell him to stop, half joking, buy always gives the excuse "she's my sister! It's ok!". Not saying you can't be rough with your sister (I definitely was as a kid), but once you're an adult, that type of horse-play usually stops.

Because he never had a brother, he has taken me as an older brother. He copies me, and loves everything I do, basically becoming obsessed with me. I love it!!! I didn't really get along with my brother growing up (6years older than me) and so it is really great to have a younger brother now.

So in May, we had been married for two months, since March. We were visiting at their home (8hr drive) after this last semester ended, we visit maybe twice a year as it's far. The visit went well, and during breakfast one morning, her brother came down stairs and as she (my wife) was sitting on a stool next to me, he puts her in a headlock. Now she instantaneously looked at me and asked for help, and told him to stop. He didn't stop for about 15 seconds, so I stepped in behind him and put him in a headlock. 

I'm in the Army, and not much bigger than him, but I am substantially stronger. He submitted and during the headlock I squoze (past tense of squeeze? Haha) hard enough for him to be choked, and I let up  (still had him in a headlock, just like he had my wife) and I whispered to him "I don't care if she's your sister. you will never put my wife in a headlock again". 

He kind of slinked down for a few hours and didn't talk to anyone. He came around and stopped feeling sorry for himself, but he was very visibly upset. 

Now, we still have a snap streak going, (his idea) and all is back to normal. Thinking about it, I was just protecting my wife. I myself went through a similar situation with my older brother in law who married my sister, and I believe that to be a very important lesson to learn.

Am I an asshole?

putting my in-law in a headlock