If you are uncomfortable with that, perhaps your T can give you a referral to other groups. It is sometimes hard to find them on your own, but your T probably knows of other therapists with groups that might be appropriate for you.

If you feel you are ready to stop therapy and don't need the additional support or structure of a group, you could just stop, which it sounds like you were prepared to do. Did your T say why he thinks you shouldn't stop therapy completely? Perhaps he/she sees some issues for you to work on that you haven't perceived?