Thanks for your response. The first thing I did when I didn't see the text message forwarding option in message settings was search "forwarding" and "text". The setting wasn't anywhere else. The search menu took me to messages, and the setting was not there.
I restarted my phone and went back to message settings and the text forward option was there. I toggled off "iMessages" because this fix has worked in the past when my Mac wasn't sending/receiving non-iphone SMS. As soon as I toggled iMessages off, the screen moved as if I had scrolled. Then I did scroll down to look for the text forward option and it was gone. I toggled iMessages back on and the option was still missing. I restarted my phone, went back to settings>messages and the text forward option was back.
After doing this and restarting my computer again and signing out of iMessages on my Mac and signing back in, I'm able to send/receive SMS from non-iphone users again.
I'll report this to apple too so they know there's a glitch. I'd send you screenshots, but I don't want to mess up my messages now that they're finally working again.