Hi Janda.
If you click on the little icon that looks like a bit of paper under Mary's name, it will say 'personal message'. You can click on this and it will allow you to send a personal message to Mary's email via Rootschat. It won't reveal her email address, but you can ask her for it, or other contact details, within your message.
That way, any personal information is only shared between the 2 of you, it doesn't show up on Rootschat.
Lovely to see that you have found each other!
Sue