I have a situation where I see my T in public on occasion. Some days I completely ignore her and at our next session it's like we weren't there at the same time, our 'run in' doesn't get acknowledged. Times when I'm feeling okay I'll say hello (I have to be the first or it breeches confidentiality) and we'll share a laugh and a little bit of passing conversation. I appreciate that any outside (or non) contact in public with T, it gets kept in that moment and never arises in the therapy room unless I bring it up.