Open the message and click on the picture in the top left corner beside "Multiple Recipients". Choose the one you want to send a message to, and it should open a new message window. Hope this is what you're looking for!
*EDIT* I just uninstalled Handcent and decided to give Go SMS a shot. Same issue, and cannot find any options to prevent this from happening.
Last edited by HarleyG33k; 10-11-2011 at 04:54 PM.
The long press to send to sender only is, thankfully, SOMETHING that can be done to prevent responding to everyone and their brother. However, WHY, WHY, WHY can't there be a permanent fix so you don't have to do this step??? If anyone hears of such a fix, please let me know! Thank you!