There’s an old saying: “There’s no accounting for taste.” You are attracted to a particular physical type. So what? Other men are attracted to a different type. So what? There are many physical types: Short, tall. Large, small. Classically beautiful, beautiful in their own way. Isn’t it wonderful that beauty is in the eyes of a beholder, not limited to one type?
I don’t know why you find physically strong women attractive. It may be that someone more muscular helped you out in some way when you were young. It may be that, shy guy that you are, you feel safe with someone larger than yourself. Does it really matter?
What I see in your letter is that you are someone who isn’t capitulating to the stereotype of what a desirable woman should look like. You see beauty where your friends maybe do not. You know that aggression doesn’t come with body type. I’m sure you know men who are large who are gentle giants and men who are small who are aggressive little roosters. Aggression is an outcome of psychology, not physical type. The same is true of women.
People who judge you are narrow-minded and prejudiced. Please ignore them. Date who you wish. It’s a sorting process. If you find someone who is aggressive, you can drop her. But if you find a large female body builder who you love and who loves you back in ways that make you feel cherished and safe, thank your lucky stars and enjoy your relationship. Chances are your relationship will be at least as good, if not better, than the relationships of friends who are so shallow that they judge a woman according to stereotypes.
I wish you well.