The issue isn’t that there is some type of taboo. The issue is that therapists have guidelines on romancing or befriending clients or former clients. Even if you feel that these guidelines are dumb and you should be able to see him in whatever capacity, it doesn’t mean HE shouldn’t abide by the guidelines. You aren’t governed by any rules. But he is. He needed to know better.

Hopeful whatever you decide will be the best outcome for you. Good luck