I think you need to stop living in the past.

For various reasons, it sounds like you were always underfoot at her house. Picture yourself in her shoes. My mother would certainly not have tolerated my brother's girlfriends hanging aroubd all the time. This was OUR house.

You two have your own place now. Start building your own life together. It should not be centered around his mother! "Your OCD" is not a good reason to be spending time online searching for stuff that doesnt exist. Spend it trying to better yourself.