Ok, Postfix is being a homo.
When I try to send e-mail in roudcube, it returns, "Relay access denied". I telnet to port 25 on the server, ehlo and rcpt from without a problem. When I enter mail to: user@domain.com it returns 554 5.7.1 <user@domain.com>: Relay access denied. Apparently, this is a postfix issue, but idk how to fix it...even reinstalling postfix from scratch doesn't fix it. Help.