Hi shady lady!
"fat and mentally ill"
This is how you describe yourself! How do you like it now that you see it isolated? Isn't it far- farfetched and over the top? I think it is. And I think you do too.
Just the fact that you haven't found a man yet and had children does it make you a failure? I think not. You are succesfull and you do the things you like and you are pretty determined and mature about your views and your goals. So why do you put yourself down as a failure? Just because you have put on weight doesn't mean you are a no-good so and so. You have a lot of other things that men find interesting, it is just that they didn't come your way yet.
If I had written your post, what would you have said to me? Wouldn't you have thought that I cannot be as bad I think I am?
Try to focus on the good things you do and happen in you life and do not fret about marriage and children. It is not that you are 85 yet!!!
Eating for confort and covering yourself with layers of fat is one way of protecting yourself from the world. Given the fact that you have such a low self esteem it seems reasonable that you still eat for confort.
Do not worry I have done this too. You ask what to do. I say, continue the gym, you are doing very nicely. Forget about men and just go on enjoying the things you like in life. The weight will stop being an issue once you stop focusing on it.
Have you thought about travelling? or joining clubs that interest you? or doing voluntary work? Then your inner qualities will shine through and will give you more confidence and the courage to start liking yourself a little better.
I am sure you will find what you are looking for once you stop looking and start concentrating on living and feeling...
God bless you!