Reported it to Apples Bug Reporter but for those who may have this happen I have a work around which will restore functionality but you will lose an entire text thread.
Some links when pasted and sent may cause Messages to hang and crash when it tries to load the preview. In my case it happened with laughitup.laughstub.com but there may be others. Safari loads the page fine. But pasting that link into Messages and sending caused an immediate crash as it loaded the preview. Each time i tried to open it, it would go to that thread since that was the last person i texted and immediately crash when trying to load new messages including the preview to the link i sent.
This also crashes the Share->messages compose screen. Though that just returns you to the site in safari.
The workaround is to use Siri to send a text to a different person to elicit a reply. Or just wait for someone else to text you. Tap the notification to jump directly to their text thread. Tap the back arrow in the upper left to go to your list of conversations and clear the history for the user that you send the broken message to. You can then talk to them normally as well as everyone else but you will have lost all history for that user.
Some links when pasted and sent may cause Messages to hang and crash when it tries to load the preview. In my case it happened with laughitup.laughstub.com but there may be others. Safari loads the page fine. But pasting that link into Messages and sending caused an immediate crash as it loaded the preview. Each time i tried to open it, it would go to that thread since that was the last person i texted and immediately crash when trying to load new messages including the preview to the link i sent.
This also crashes the Share->messages compose screen. Though that just returns you to the site in safari.
The workaround is to use Siri to send a text to a different person to elicit a reply. Or just wait for someone else to text you. Tap the notification to jump directly to their text thread. Tap the back arrow in the upper left to go to your list of conversations and clear the history for the user that you send the broken message to. You can then talk to them normally as well as everyone else but you will have lost all history for that user.