Trying to let go

Right now, I'm trying to let go of my main online friend group. They're not toxic or anything, but I've had some problems with them in the past that affected my overall self esteem and health. They just seemed too negative. I left their main group chat in July, but still kept in touch. However, deep down, I've generally sort of disliked the group chat and aspects of it to a point where it became frustrating. At a point I even distrusted them deeply and feared they would shun me out or talk about me secretly. I decided instead of trying to keep fixing it over and over was to just move on. I've started this only a few days ago, but it already feels agonizing. I keep feeling doubt and unsurity, but I feel deep down that this is right. I'm thinking of becoming very distant from them and quiet until I'm eventually forgotten about. I have seasonal depression and have wondered if it's making me feel like this. Advice?

Also, I hope I don't sound mean or ungrateful. I'm not good at expressing my emotions cleanly