VlaudTheImpaler
tl;dr
OP, I use to have the EXACT problem as you my friend. I even avoided playing certain games with my wife (Resident Evil 5 is one ironically) because I was insecure. I was always kinda chubby and worked out like crazy and barely saw results. My favorite hobby became a source of shame and self loathing.
I'm honestly pleased to see you open yourself up and be honest about it. Especially on a forum with a lot of brutally unkind/insensitive people.
I just wanna say that it all comes to how you eat. Working out is a small part of it. It's not even about restricting calories, it's about the quality of your food. I for example went vegan not too long ago, eat a lot more than I ever did, and now I'm 20lbs lighter than when I started and still going.
Also check out FitnessGaf in the off topic community section. Great guys (nerds) that are in great shape. They won't berate you, but would be glad to help.
Btw, it also helps to realize that it's simply more appealing to have characters that are healthy looking and capable of feats of athletic strength. Games, especially action games, will lean towards that ideal. They arent trying to be offensive. They can certainly be extreme towards both genders, but just think of them as healthy, NOT as sexy.
Hit me up in PM's if you wanna talk. I feel for you and have been there.
YES! I came to say this and then read your post.
Seriously though, Whenever I play as a protag that is ripped or whatever, it has always inspired me to be more healthy. It had a big impact on me when I was younger. I would play through a section of a game like halo or something and even though I knew I could obviously never reach that level of fitness, it always encouraged me to do as much as I could and man, I will forever be thankful of that.
One thing I think would be awesome to promote health would be to see some transformative stories where the protag goes from really unhealthy in the beginning to healthy in the end where the character would change drastically. I can imagine several awesome scenarios off of the top of my head where something like this would fit really well.
For example, imagine a post apocalyptic game where you start off as an overweight/severely underweight unhealthy male or female and as you survive you deal with all sorts of random yet realistic health problems but struggle to overcome them. As the game goes on you gradually lose the weight by necessity and your character starts to transform into a healthy looking survivor. I think it would be cool if some sort of mechanic could be worked into it where the more you do with your legs the more fit they become and so on.
All of this would be cool but more importantly informative to the struggles and limitations that those who are not healthy endure and have to overcome. Would maybe put a different perspective in the minds of those who are tempted to shame and bully while at the same time inspire those who are living in an unhealthy state to try to do something about it if there is anything that they can do.
One thing I would agree on with OP though is ethnicity and facial/body structure. I would like to see more interesting character faces and races in AAA games. More akin to what we see in TV shows and such these days.