Emotions? what are those? totally overrated...
Have they considered any medications for you in short term that might help? I was on paxil when I was a teenager, it turned me into a zombie... no happy, no sad, no pain, no joy, no libido... zilch, nada, zero. Not saying that who you are and how your emotions react are a 'bad' or 'good' thing, its just you. But, if the people who are performing your surgery think it is, sometimes you just have to suckit up so you can make it happen. Since most of us here are in our 20s and obese (or formerly)... odds are most of us went through our childhoods as the "fat kid"... thus our emotions have developed in that type of environment... some of us grew a very thick skin and dealt with it and today are still very defensive (myself)... some of us took every pick/knock personally and simple things today trigger an emotional episode... some of us are just drama queens or feel everyone is out to get us.
Regarding your examples... and the little that I have studied psychology. Both your examples exhibited dependancies on another person or an inanimate object as a security blanket. Both of those behaviors of not letting go of things, in turn will likely make you more suseptible to not letting go of your old and poor eating habits and to choose to alter your life to the degree that it may be completely different than it is now. As such, if you hold onto the memories of your grandmother to the point where you feel it will (spiritually or whatnot) make your surgery go better by having a ring around your neck, you're transfering your worries and copeing skills onto something you have no control over. However, if you elect to suck up your emotion, put her ring in the drawer at home and say "self... we're doing this for me, not Aaron, not grandmother... I'll be just fine"... it'll get your 'psych'ed' up to accomplish your goals. I know that -you- may feel that your 2 emotional responses to the examples you gave are completely valid, justified and warrented... but how do they appear to others... that is the question. If a doctor feels you're a basketcase because of those responses... you just need to hide yourself a little better in the next week to get the surgery done. Even if you admit to them, but maybe not yourself, that you overreacted... that's all the confidence they need to see in order to give you the green light.
So now... you might tell me that you are ready and you aren't really thinking like this... But I'm not the judge and jury... its the medical professionals who are supervising your surgery. They get to decide if you're ready and have jumped through hoop A and B and C.
It's up to you to prove to them you are ready even if you think it's silly. Which is another emotion that is triggering that defensiveness about you feeling that it's silly...called ego...