Why would you be talking to your T out of session? I mean, you might happen to run into her on rare occasions, but the most that really happens then is you say "hi" or a quick nicety and go on your way. She won't stand there and have a long conversation with you. And generally they won't make first contact outside their office even if they see you. They wait to see if a client wants contact.

I've seen my T now for 9 years and have only run into him 2 or 3 times. It wasn't a big deal, but it was just a quick "hi, what ya' up to" and on our ways.