I'm sorry things are rough at home. I can't imagine how it must feel to have your husband leave you and your family. Did your family come through and help out?
About sleep, I've heard that some people have trouble with naps once night time sleep gets better. I think it is a phase, and it also could be related to age. I'm having a hard time with naps all of a sudden and Daniel loves to nap. He's just so busy, he doesn't want to stop and sleep. In your situation I think you should adopt the phrase "by whatever means necessary" when it comes to naps. Does she sleep in the car? If so, take some long drives with her. If you get her really sleepy in there, she might go down easier at home, or she might just take her naps in the car. You could also try the carrier, though I've never had any success with that. Does she sleep in the stroller?
I really, really hope things get better for you soon.