You might be confused about how a forum works. You can't just order people to leave because you started the thread. It's a conversation, not a soap box.
Well actually... you CAN order people to leave. How's that working so far?
If you have a problem with somebody there are multiple avenues of relief:
1. File a complaint with a moderator.
2. Put the person on ignore. This means you will not be able to see the person's comments.
3. Just roll with it. Life happens, there are parts of it we don't like, and we don't get to make every part of it suit everybody all the time.