OK, so the problem is that using the PHP mail function and sendmail you can set the From: address in the contents of the email message but you can't on the envelope. The web server becomes the sender of the email which is why the MAIL FROM: in the envelope is being set to apache.
So I see two choices:
1) Don't use the built-in PHP mail functions in the script but rather use something like PHPMailer which is full featured email transfer class for PHP.
2) Configure your machine correctly to have the right domain name (not localhost.local) and then forward all emails from the apache account to yourself using the .forward file.
I hope that helps,