If all my clients would adopt an attitude like yours my work would be a lot easier. Most people come to me with no idea about nutrition and feel the need for me put them on a tortuous exercise program like they see on shows like the biggest loser.
No-one has to beat themselves up to lose weight and as you've said exercise isn't even mandatory. The diet is where real changes need to happen.
You've got this man, I'm sure you're going to be in top shape in a relatively short time.
RE: 2018 weight loss challenge weekly weigh in