Think back to the first day you felt like this. Then carefully comb through the week previous to that, and catalog everything that changed during that time. That includes "one-off" events that are not normal, that effected you emotionally when they occurred. Like "My husband's sister came over, and really upset me by doing such and such".
Perhaps that will help you find the source.
The source is 2 weeks ago my SIL had a baby. Another baby. Another baby with no father, I should add. This is a huge source of conflict for me because her decisions concerning children violate my entire moral code. (I don't think any more detail on this is required, but I can give it if anyone needs it for clarification.) In sum, everything I believe in she and his family don't. (My husband is the exception... Otherwise I never would have married him.)
I know I can't tell people how to live their lives and everyone is entitled to their own beliefs, but I don't want to be around a group of people that aren't on the same page as me concerning finances, child rearing, housekeeping, spousal relationships, health, etc. I've always differed from them on this and my husband says he "wants" to be like me concerning these life approaches, but sometimes, I doubt him. Or, I'm terrified he doesn't actually want what I want. Up until this baby we had put sufficient space between them so I thought things were OK, but now he wants to go there every weekend. No. I don't want to spend my Saturdays like that. When I tell him to go without me he gets SO upset. His sister's husband doesn't get on with their family either and he NEVER goes to any social calls, events, etc. I'm jealous of him, too - although I'd never want the relationship he and he wife have, but that's another issue altogether...
I think that's why I'm rebelling by being lazy. I want him to tell me it's not OK to come home, hop into my pajamas and sit on the couch. There's dinner to be made, a house to be cleaned, a dog to be walked, sex to have, etc. This is how his 2 sisters and mother live and I always told him how unfitting for ME it was. (His mother didn't work at all and played Candy Crush all day, just to give an example.)
Now that this is all off my chest, I need to STFU. Like the above poster's tagline: Not my circus, not my clowns. They're not going anywhere so I need to learn how to cope. I don't need my husband's validation. It'd be nice to have, but the only person you have in this world is yourself so I need to embrace that without resenting my husband. As far as husbands go, he's more useful and attentive than most so although this is a big issue, it's one issue and I have to let it go. It has to start with me and my attitude.
I'll go grab a coffee and Google roast recipes. We have an awesome roast I should have cooked, but didn't have the appetite or desire to do so. A roast will be nice on a day like today.