"Yes, you did tell me many reasons why you thought I shouldn't date him, but I took it as you sharing your opinions, as you are certainly entitled to your feelings about what went on between the two of you. I didn't know you meant that you would be upset and end our friendship if I didn't do as you said."
Four years do not breed "opinions" or "feelings" about what went on... it was fucking fact.
How can it be so hard for you to understand?