I believe that grieving after loss of your therapist continues even after the last session. But I realize now that it can be fatal if you don't get the opportunity to start grieving and realizing that it is over till after the therapist is gone for ever. If you don't get the opportunity to say goodbye to your therapist in mutual understanding and honesty. If it was because he had died I might be able to handle it.
After 18 years this doesn't feel just like a blow. It feels like a disaster. I see nothing but ruin.