Don’t involve yourself with anybody that mocks your stutter, I mean they should obv know it makes you feel like shit it’s pointing out an impurity and I’m sure everybody has their own. Don’t just sit there and pretend like nothings happening while your inner self is going turmoil. For example if you don’t like their shoes point at them and be like what are those bro! What dumpster did you find them. Surely it will turn into a more comfortable setting being that the mocker can also be mocked.