Why do you think it's now related, in part, to a guy (it feels tainted)?

I think what's happening is that you seem to lack control of certain aspects of your life and by you controlling your eating you are trying to make up for these other areas which you cannot control. This is a serious recipe for major problems with anorexia which could become a very problematic to your life and your health if you do not learn to handle these intolerable aspects of your life.