Just read your thread and it brought back so many memories for me. I can now admit I really struggled post natally after my second baby, mentally far more than physically. I too focused on what my DH was doing, and remember bursting into tears when he wore his contact lenses (he usually wears glasses) because it was sunny and he wanted to wear sunglasses, I had imagined he was off seeing another woman and was getting dolled up!
You know are not bring rational but can't stop yourself being like this at the moment. This is because you are a new post natal mum. You are also adjusting to having to deal with two children, yes it is tougher than dealing with one, but you are a strong woman and can and will cope with this over time. This is a period of adjustment for your whole family, and it sounds like the lack of stable contacts, health professionals and environment is contributing to your current state of mind as well.
It's really important to know this state of things will improve, try not to be too anxious about it, and and others have said, be as kind as possible to yourself while you think this way. Your will need to be monitored by someone (often health visitor or GP) to make sure these normal feelings do not persist or become more than a transient post natal depression, your midwife will hopefully offer to monitor you until your health care providers arrangements are more stable.
It sounds like your DH isn't quite appreciating what he needs to do to help you at the moment. I would suggest asking him to complete a list of specific tasks, if he's military they usually respond well to that! One of those should be taking sole care of your LO for a couple of hours after a feed so you can have a shower and a nap, with orders not to wake you until she is ready for her next feed. Lack of sleep makes everything seem worse than it is, so sleep for you has to be a priority at the moment and will contribute to your overall sense of well being. I sincerely hope you start to feel better soon, I really feel for you.