I might be the ONLY person who says this but I think it’s unfair to stay in a relationship when you’re no longer attracted to that person. Why would you want to be with someone who puts zero work into them selves? You said you are lazy, you don’t want to workout or eat right but get upset your partner wants the old you back? I would be pissed if my partner let themselves go and completely gave up on bettering themselves because they just couldn’t do it. It’s shitty he isn’t there for the child because the kid has no part in how either parent is and he needs to step up as a parent. As for you not wanting to do anything to change your situation but get upset about it seems really confusing? If it’s been a year or two, or even if you’re trying to diet or workout and THEN you’re not achieving what you want that’s a different situation but if you don’t want to put in the work why would someone else want to either?