Maybe just sitting down and having a plan for how it will all come together eventually will help? Then I'd focus on one space at a time, I'd probably try to do the most-used room by the family right away or the space that you can retreat to that isn't too big so at least you can have one room that feels homey, not sure which one that is, probably the TV room or living room or maybe your bedroom? I would leave the basement alone or to the end if it isn't bothering DH. Paint really is pretty inexpensive and just transforms a room, so I would probably start there with whatever you can do, and hey you won't have all that furniture to move to paint, right
And you can get artwork/prints/etc. pretty cheap if you keep on the lookout at garage sales/thrift stores/etc., etsy is a good resource or just whatever local artists you might be able to find. And I've found curtains to often be fairly inexpensive too, so that might be another good thing to do in your first room right away.
I just think having a plan and getting one room nice and homey might make you feel better about it. I know as long as I have a retreat, I can stand a lot in the rest of the house as long as I know it is temporary.