whoops jealous

Okay so Ive been having some serious jealousy issues lately. My partner and I are super long distance (US &Sweden) and I'm staying with him and his family for the holidays. But we keep coming back to a really big issue and it's that I'm not comfortable with him hanging out with girls. He says he doesn't see gender or whatever but it just keeps getting me angry and anxious. I know he's not doing anything wrong and I know it's all in my head. But it's getting so bad like. Ugh. I'm so frustrated bc I love him and I know he won't do anything to hurt me but I just get set off so easily. And tbh I haven't been like this in the past. I guess with the distance I wanted a lot of attention and I get worried he could find someone without all my issues but I don't want it to affect my time here. And it is. And I don't want it to. I'm really starting to dislike myself.