I agree with Stacey I would mention it before doing it. Also, are you sending non work related texts? You mentioned you’re the “star player” so I assume, all your work is being completed in a timely manner. It probably shouldn’t be this stressful. Do you have an underline anxiety issue?
If it's a work line he has every right to be included on it. Sorry but it's the truth. The work line should only be used for work purposes. It shouldn't bother you unless your using it for personal reasons as well.
Why is it so upsetting? Does he know you’re feeling like this? I would tell him about the anxiety before just kicking him off without explanation. It might raise flags if you do that.