How do your partners handle you training? Are they comfortable?

I (20F) am seeing a guy. He doesn’t train. He’s saying that he isn’t comfortable with me training jiu jitsu. Basically he saw a video of me hip bumping and trying to get my 120 kg opponent off me when im at 50 kgs. He thought it looked sexual. Tbf it did. And now he’s liek I don’t want the girl I’m dating to be humping grown men. I can’t explain to him that it’s not sexual. And since I’ve dated 2 guys from gym before he’s even more insecure and worried. I even suggested he try training one class and see it’s not sexual. But he’s not even open to that. Have any of you encountered that problem?

Edit: his ex finance cheated on him with multiple guys some from the gym and work. They were all “just friends” too in her case. In my case they actually are but still I get his insecurity.

Edit 2: we just discussed it. He says he accepts me as I am. And he wouldn’t tell me to quit something I love to be with him. As long as it makes me happy he trusts me and he’s ok with it.