[RogueCoder]

I don't think you should be ashamed of your scar. It proves you're a strong person who had to fight for his life and won. It's going to take some time to get used to it, sure. But it's still a part of you. There's a saying; Fake it till you make it. What it means is that you can trick your brain into actually believe what you tell it. But before the brain accepts your "lie" as the truth you must fake it.

Even though you might feel ashamed, take of the shirt, smile and be proud to be a live. You will see that in time the feeling of being ashamed will go away.