Yes, you are correct, and I believe the relationship has ended on its own. Ever since I told him I was not comfortable with the "trio," he has ceased to contact me...and I am fine with that. You are right on the nosey when you said he was too rigid and uncompromising and would make everything out to be my fault. That is exactly what he does. And I do not deserve that. Unfortunately, I tend to see only the good side of people and not the bad...or perhaps I do not pay attention the bad. I try to give everyone a chance, and in many cases, I give too many chances.
What is really difficult about the situation is that I AM friends with the girl. She is very nice, fun, and I sort of see myself as something of a big sister to her. She also just found out she is going to be leaving for an internship in the Northeast next semester, which will be a FANTASTIC opportunity for her. I wonder, when she is gone, whether this guy will come knocking on my door again. You can be certain that if he does, I will NOT be at home!
Thanks everyone. Your suggestions and support are very much appreciated, and have reaffirmed my belief in my own intuition.