You never thought you would find a girlfriend, so when the first girl took an interest in you came along you agreed to do anything for her. Now you are seeing what she really meant by anything.
You always thought you had problems with being insensitive down there, however, it would appear you just jerked off too much and lost sensitivity, 2 months in chastity fixed that.
Signing up for a medical kink weekend was on your dream list. The chastity belt was a nice touch, but the full denial was starting to really get to you, you cant remember the last time you went longer than 12 hours without orgasming.