Like you, I've been big my entire life and told the same things, and it's really hard to push that out of your mind. However, there's no way I could have achieved the things I did unless I learned to love and accept myself—I'm talking about before my weight loss.
When I started my undergrad I came to terms with my size and I really decided to just live for me. I changed from a shy girl who tried to hide into a confident young woman who wanted it all. I saw so many confident women who were much larger than me and I decided that if everyone could accept their awesome personalities over their size, that MY personality would be the determining factor in how people thought of me too.
Because I loved myself, everything fell into place. I met the man I will wind up marrying and he has loved me at my highest weight and now as I'm losing weight.
I've had numerous academic achievements and job-related achievements, I have a great group of friends who have been with me through thick and thin.
And honestly, it was only because I loved myself that I really began my weight loss journey. When I hated myself and what I looked like, I only gained weight because I couldn't muster the motivation to do anything about it.
My advice? It may seem counterproductive, but look at size acceptance blogs and sites. You will see confident large women surrounded by people who love and care for them. Their amazing personalities shine through and I swear you can just see it on the smiles in their pictures. Hopefully they will inspire you to love YOU just the way you are.
It really looks like you have two journeys to complete; one of weight loss and another of self love. I wish you all the best luck and that you will emerge as a confident person who can tackle anything