It's Gonna Fuck Up My Relationship

So my mom doesn't like the guy I'm dating. He's loud and he cusses (not towards her or around her, but she overheard him on the phone) his mom was a teenage single mom so there's a lot of things about being a gentleman that he doesn't know and I don't blame him for that because he tries, but my mom is so...stubborn. she says it's not my job to help him learn these things, but why wouldn't I? Also he jokes a lot, like yesterday she wanted to know what time he was coming to get me and I didn't know because he said 7 pm, but I knew that wasn't the case he was just joking. She went off on a tangent about how he was waiting to hear back from another female and that he was playing me and that I needed to drop him and I know for sure that wasn't the case, he's just stupid. Anyway her yelling in my ear about all of this frustrated me to the point of tears because she always has to be right so I called him kinda with an attitude asking him when he was coming and why he couldn't just answer simple questions the first time so I wouldn't have to deal with that shit and then he proceeded to tell me he was on his way 🤦🏾‍♀️ and then he said it feels like he's dating me and my mom because I transfer my attitude with her to my conversation with him and I don't mean to but ITS FUCKING IRRITATING. She even tried to say that he would stoop to putting his hands on me and I know he never would . He's the nerdiest of nerds, and chill. Only reason he's loud and cusses is because he's obnoxious, it's never in a serious manner. She doesxn't know him and she jumps from conclusion to conclusion and then I end up snapping and going off because it's wrong to judge people like that. I just can't win 🙄 anyone know what I can do?