I have the same thing. Being a big person, I've always tried to dress down my weight. For me, that means shirts that hang straight down from my shoulders - to minimize the love handles etc, and loose shorts or pants to hide the bottom half.
But, I've gotten over that for riding. Once I put on my cycling shorts, jersey, helmet, sunglasses, etc. I feel almost like I am in disguise.
I have ridden past my spouse, my mother-in-law, and my uncle, (all on seperate occasions) as they were driving and not one of them realized it was me on the bike. I had to stop and flag them down to get their attention. And all of them told me they didn't recognize me.
So.. what I'm getting at is. If no one knows who I am, I don't care what they might think about me.
It doesn't change the way I feel when I look in the mirror, but it helps me not to worry about it when I'm on the road.