As someone who fully divested from twitter despite being reliant on it early in 2023 I'm here to tell you that you can, in fact, just not use twitter. You can go all in on mastodon. In fact, it'll probably make mastodon work better for you if you do
same....the first couple weeks were hard and I had the urge to check Twitter a lot, but I dealt with that by uninstalling the app on my phone so the only way I could check it was to log on via the website which was unpleasant and annoying enough to break the habit. At some point I stopped thinking about it alltogether.
I had mostly stopped posting there a while before I left though and didn't post anything at all there after I decided to leave, so there was really nothing drawing me back once I broke the physical habit of checking the Twitter app on my phone.