Clearly. You knocked on the door, showed her your wares and she cast you off like a used prophylactic.
You see, she could tell by your withered excuse for a copulatory member, that you were not good breeding material and decided that she would stick to what she knew...so to speak.
As for my (now ceased) regular intrusion of your Girlfriend. Did you never wonder why it was like shaking a stick in an alley? I bet you just assumed she was "loose" and Wizards Sleevelike. How very unfair of you. It takes time for a lady to shrink back down you know mate.
"Ouch!!"