It's a fact that your spouse finds someone else attractive. It's getting them to admit it to you that is the problem. that is of course if you want to know the truth.
What I have found out is the direct opposite of you. I am by no stretch of the imagination even close to your build or will probably ever be but aws i've grown bigger my wife tells me she hates it. I thought she was just telling me these things at first(i dont like muscles etc etc) to be nice but over the past year or so she lets me know her down right disgust of people like cutler, coleman and priest(three guys I look up to as far as BB goes)
You should be happy because the chance of her finding other body builders bigger than you is much slimmer than my wife finding some skinny guy.