Mom always wants to argue??

So today my younger sister had her birthday party at a big arcade type place, and it was a ton of fun! But, at the end my mom and I got in this big argument. We were going bowling and I was messing with the machine to remove a name like we had all talked about, but all of the sudden my mom starts yelling at me to stop. So I tried explaining and she just told me to stop and leave it alone. I was feeling pretty embarrassed at this point and just went with my boyfriend to go sit down with everyone and not mess with the game. 5 minutes later my mom says “well now your sister is sitting over there all fucking moody” and I ignored her. Then she said it again but this time louder and while looking at me. I said something along the lines of “I wasn’t even saying anything to you, I’m just sitting here” and my boyfriend said “she’s just on her phone”. She told my boyfriend to shut up and then kept yelling at me for no reason about how I’m “always like this”, and I started crying because it feels like no matter what I do I’m the bad guy. After that I just walked away and I could hear her continuing to talk shit about me to my entire family. I guess the reason I’m posting this is to get some ideas on how to handle this in the future? I feel like my mom constantly wants to fight over nothing. It’s only getting worse and I’m just so over it, even after that she went near me in this huge game place to take a “family picture” without me in it. Right next to me. Plus her telling my boyfriend to “shut up” was crossing a huge line for me.