Oh apple that's so sad to read. Why is your DH not backing you up re the way your children talk to you? It seems as though all the relationships in your home have soured - you are probably finding it hard to show your love to the DCs, and no wonder, they are certainly not showing any to you.
I do suspect, though you didn't want to talk about it, that your DH is disrespectful to you and the DCs are taking their cue from him.
If he treats you like the DCs treat you, you should not put up with it. Seriously. If my DH treated me like that I would not be able to stay married to him.
And if he doesn't disrespect you, and isn't as bad as I am fearing, he also needs to step up and show a united front to the DCs. If there is conflict or stress in your relationship perhaps the reliable base for the kids is not there, and its possible that they are kind of testing their safety by testing you?
But on a less deep note, you have done great to lose that weight and get into good routines and love yourself. You need to stick at it, not just for you, but to show the family you respect yourself and prioritise yourself.
And don't tidy their rooms. Let them lose stuff. It's their fault if they do.
hugs for you - focus on yourself. You have to care for yourself, because you absolutely deserve it, and your kids' mum deserves it too for that matter. Whatever your parents might have taught you. They w ere wrong.. you know that, don't you?