oh my goodness my T and I just had a similar discussion this morning!!!
Last week I got in a particularly bad situation (medically) and ended up texting her and then she ended up calling me to make sure I got the help I needed. I felt SOOO bad having taken her time outside of work, and worrying her like I did, that I spent the first five minutes of my session just apologizing - and then wrapped up the session with some more apologies despite our prior conversation on how it was unnecessary!
I also am not sure how to stop apologizing. If you find out how, please let me know