My (26F) boyfriend (27M) keeps talking to other people on discord

We met in a discord socializing server, and it’s been 2 months into the relationship and I have never felt the way I feel with him before with anyone else. He says he’s planning to meet me soon. Usually things get really sexual, or we talk about really interesting things and the conversations go on for hours.
However after a month or so after talking, I saw him on the server talking to other people on 2/2 VCs. I never felt the need to do that after meeting him, not because I don’t have a social life – I am extroverted and have a huge circle in real life – but because I am fulfilled with him and don’t feel like going on those servers again. I told him that it’s weird to me that he’s still going there, and he said he understands and won’t do it. A few days later I saw him there again and it didn’t sit right with me, so I brought it up again and he said he’ll leave the servers and left them.
Everything was going well, but the day I was flying to another country, I opened my chat to text him one last time before the plane took off and saw him in 2/2 VCs again. This time it just ruined my day.
I too joined those VCs later twice, and not because I wanted to – but because I wanted to see his reaction (I know, it was pathetic) and if he’d feel okay with me talking to a bunch of weird people there, and during one of the sexual sessions, he brought up how he hated seeing me there because he loves me. I told him I’ll never go there again, and I never went there again.
Today morning, I saw him there again and for once, I decided to not continue the relationship with him further.
Something about it makes me feel weird – it’s something so simple for him to follow or keep his word with, but he says he’d rather want to shift to other places to talk because he can’t control talking on these servers every now and then.
I can see his point that he finds fun people to talk to, broadens his horizons and stuff, but why don’t I feel the need to do that?
I can’t believe I’m feeling insecure or jealous over this, I’ve never been this way before. I told him I’m taking a break and assessing my own actions because I know I’m being controlling and I’m not able to stop myself. So it’s better if I go off and process it.
I’d appreciate some insight, thank you.

TL;DR: my boyfriend talks to 2/2 VCs on discord servers where we met and it makes me uncomfortable, but he doesn’t stop.